EPA/540/R-03/505
                                     July 2003
           Evaluation of
Wilder Construction Company's
  MatCon™ Cover Technology
 Innovative Technology Evaluation Report
          National Risk Management Research Laboratory
            Office of Research and Development
            U.S. Environmental Protection Agency
               Cincinnati, Ohio 45268

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                                                 Notice
The information in this document has been funded by the U. S. Environmental Protection Agency (EPA) under Contract No.
68-C5-0037 to Terra Tech EM Inc. It has been subjected to the Agency's peer and administrative reviews and has been approved
for publication as an EPA document.  Mention of trade names or commercial products does not constitute an endorsement or
recommendation for use.

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                                                 Foreword
The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air, and water resources.
Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible
balance between human activities and the ability of natural systems to support and nurture life. To meet this mandate, EPA's
research program  is providing data and technical support for solving environmental problems today and building a science
knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect our health, and prevent
or reduce environmental risks in the future.

The National Risk Management Research Laboratory is the Agency's center for investigation of technological and manage-
ment approaches for reducing risks from threats to human health and the environment. The focus of the Laboratory's research
program is on methods for the prevention and control of pollution to air, land, water and subsurface resources; protection of
water quality in public water systems; remediation of contaminated sites and ground water; and prevention and control of
indoor air pollution. The goal of this research effort is to catalyze development and implementation of innovative, cost-ef-
fective environmental technologies; develop  scientific and engineering information needed by EPA to support regulatory and
policy decisions; and provide technical support and information transfer to ensure effective implementation of environmental
regulations and strategies.

This publication has been produced as part of the Laboratory's strategic long-term research plan. It is published and made avail-
able by EPA's Office of Research and Development to assist the user community and to link researchers with their clients.
                                                    Hugh W. McKinnon, Director
                                                    National Risk Management Research Laboratory

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                                             Abstract
To enhance conventional paving asphalt to make it more suitable for containment applications, Wilder Construc-
tion Company of Everett, Washington, developed MatCon,™ a polymer modified asphalt system. The system is
comprised of a proprietary binder, coupled with a selected aggregate type and gradation, and a specialized job mix
formula.  This system, when applied using installation specifications, results in a potentially superior substitution
for conventional paving asphalt in cover containment applications.  Under the U.S. Environmental Protection
Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program, the system was installed for evalua-
tion at two locations, with another possible in 2003.

MatCon™ is intended for use as a waste containment material, to comprise a single or multiple layer cover sys-
tem. MatCon™ is noted for its superior engineering qualities and is designed for long-term performance, yet can
be applied with conventional paving equipment. The hydraulic performance of the material was examined by
both removing destructive samples for laboratory testing, as well as field evaluation. While the study focuses on
hydraulic properties, accompanying engineering properties were evaluated in the laboratory.

An important benefit of MatCon™ is the potential for multi-use as parking, storage of materials, and even recre-
ational sites such as tennis courts, created by the more durable  surface that does not need to be covered by soil or
other protective materials. MatCon™ contributes to improved  properties over conventional asphalt by rendering
the binder less susceptible to deformation or rutting and less likely to crack in cold climates. The short-term re-
sults of this testing show that MatCon™ specimens were not adversely affected and conventional asphalt mixtures
deteriorated over the 100-day test duration.

This is a long-term research effort, but preliminary results from both laboratory and field surface ponding tests
show that the MatCon™ cover system yields hydraulic conductivity results that meet or exceed fundamental
baseline targets for RCRA Subtitle C cover systems. Research will continue to assess performance over the long-
term.
                                                   IV

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                                         Contents
List of Figures and Tables	vii
Acronyms, Abbreviations, and Symbols	viii
Conversion Factors	ix
Acknowledgments	x

Executive Summary	1

1.0    Introduction	4

        1.1     Description of SITE Program and Reports	4

                1.1.1    Purpose, History, and Goals of the SITE Program	4
                1.1.2    Documentation of Site Demonstration Results	5

        1.2     Purpose and Organization of the ITER	5
        1.3     MATCON™ Process Technology Description	6
        1.4     Key Contacts	6

2.0    Technology Applications Analysis	7

        2.1     Site Demonstration Objectives and Conclusions	7
        2.2      Feasibility Study Evluation Criteria	11

                2.2.1    Overall Protection of Human Health and the Environment	11
                2.2.2    Compliance with Applicable or Relevant and Appropriate Requirements	11
                2.2.3    Long-Term Effectiveness and Permanence	11
                2.2.4    Reduction of Toxicity, Mobility, or Volume Through Treatment	13
                2.2.5    Short-Term Effectiveness	13
                2.2.6    Implementability	13
                2.2.7    Cost	13
                2.2.8    State Acceptance	13
                2.2.9    Community Acceptance	13

        2.3     Technology Applicability	13
        2.4      Limitations of the Technology	13

        2.4.1   Site Characteristics	13
        2.4.2   Quality Control	14
        2.4.3   Site Reuse	14

3.0    Economic Analysis	15

        3.1     Site-Specific Factors Affecting Cost	15
        3.2     Basis of Economic Analysis	16
        3.3     Cost Categories	16

                3.3.1    Site Preparation	16
                3.3.2    Permitting and Regulatory Costs	17
                3.3.3    Labor Costs	17
                3.3.4    Supplies and Consumables Costs	17

        3.4     Cost Per Acre of MATCON™ Cover	17

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                                Contents (continued)
4.0    Technology Effectiveness	18
        4.1     Description of the Installed Covers	18
                4.1.1    DAFB Site	18
                        4.1.1.1   Cover Installation	18
                        4.1.1.2   Drainage System	18
                4.1.2    Tri-County Landfill	24
                4.1.3    Installation Difficulties	24
                        4.1.3.1   Subgrade and Drainage Systems	24
                        4.1.3.2   Cover Construction Quality	24
        4.2     Evaluation Procedures	24
                4.2.1    Field Testing	29
                        4.2.1.1   Basis of Measurement of Field Permeability	29
                        4.2.1.2   DAFB Site	29
                        4.2.1.3   TCLSite	29
                4.2.2    Sampling Methods	29
                        4.2.2.1   Sampling Obejctives	30
                        4.2.2.2   Sampling Locations and Procedures	30
                        4.2.2.3   Sampling Identification and Handling	30
                4.2.3    Laboratory Testing	30
                4.2.4    Quality Assurance and Quality Control Program	30
                        4.2.4.1   Field Quality Control Program	34
                        4.2.4.2   Laboratory Quality Control Program	34
        4.3      Site Demonstration Results and Quality Control Program	34
        4.4      Discussion of Results	38
                4.4.1    Discussion of Field Data	38
                4.4.2    Laboratory Data	38
5.0    Technology Status	44
        5.1      Commercial Liability	44
        5.2     Construction Quality Assurance Requirements	44
6.0    References	45

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                                 Figures
2-1    LOCATION OF DOVER AIR FORCE BASE	8
2-2    SITE LOCATION, TRI-COUNTY LANDFILL, ELGIN, ILLINOIS	9
2-3    SITE LAYOUT, TRI-COUNTY LANDFILL, ELGIN, ILLINOIS	10
4-1    MATCON™ LINER AND COVER SYSTEM	19
4-2    LOCATION OF DRAINAGE AND METERING PIT	20
4-3    MATCON™ LINER AND COVER SYSTEM CROSS-SECTIONS A-A AND B-B'	21
4-4    DITCH CROSS-SECTION	22
4-5    MONITORING PIT/FRENCH DRAIN	23
4-6    MATCON™ LINER AND COVER SYSTEM LEAK DETECTION SUMP	25
4-7    PLAN VIEW OF THE MATCON™ COVER	26
4-8    SECTION A-A	27
4-9    SECTION B-B'	28
4-10   SAMPLING AREA LOCATIONS	31
4-11   CURVES SHOWING DEFLECTION VS. TIME	40
4-12   FRACTURE STRESS (MPa) AND TEMPERATURE (C) FOR MATCON™
      AND CONVENTIONAL MATERIAL	42
                                 Tables
2-1    SUPERFUND FEASIBILITY EVALUATION CRITERIA FOR THE
      MATCON™ TECHNOLOGY	12
3-1    ESTIMATED COSTS ASSOCIATED WITH MATCON™ INSTALLATION	16
4-1    COVER SAMPLE TYPE, NUMBERS, AND LABELING - DAFB SITE	32
4-2    CHARACTERIZATION TESTING ON ASPHALT SAMPLES -DAFB SITE	33
4-3    ESTIMATED IN-FIELD PERMEABILITY OF MATCON™ COVER
      DURING RAINFALL EVENTS	35
4-4    STATISTICAL SUMMARY OF LABORATORY DATA	36
4-5    TENSILE PROPERTIES FOR BINDER AND MIXTURE AT COLD TEMPERATURES	40
                                     VII

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          Acronyms, Abbreviations, and Symbols
ASHTO
AMRL
ARAR
ASTM
cm/sec
COE
CQC
DAFB
DLS
EPA
HOPE
ITER
MPa
NRMRL
ORD
OSWER
PG
PRI
PVC
QA
QC
RCRA
RPD
SARA
SITE
TCL
TEP/QAPP
TER
UV
wcc
WMI
American Society of State Highway and Transportation Officials
Asphalt Materials Reference Library
Applicable or relevant and appropriate requirement
American Society for Testing and Materials
Centimeters per second
U.S. Army Corps of Engineers
Construction quality control
Dover Air Force Base
Drainage layer sump
U.S. Environmental Protection Agency
High-density polyethylene
Innovative Technology Evaluation Program
Megapascal
National Risk Management Research Laboratory
EPA Office of Research and Development
Office of Solid Waste and Emergency Response
Performance grade
PRI Asphalt Technologies, Inc.
Polyvinyl chloride
Quality assurance
Quality control
Resource Conservation and Recovery Act
Relative percent difference
Superfund Amendments and Reauthorization Act of 1986
Superfund Innovative Technology Evaluation
Tri-County Landfill
Technology Evaluation Plan/Quality Assurance Project Plan
Technology Evaluation Report
Ultraviolet
Wilder Construction Company
Waste Management, Inc.
                                    VIM

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                              Conversions
                  To Convert From
                            To
                     Multiply By
Length
Area:
Volume:
inch
foot
mile
square foot
acre
gallon
cubic foot
centimeter
meter
kilometer
square meter
square meter
liter
cubic meter
2.54
0.305
1.61
0.0929
4,047
3.78
0.0283
Mass:
pound
kilogram
0.454
Energy:
kilowatt-hour
megajoule
3.60
Power:
kilowatt
horsepower
1.34
Temperature:
("Fahrenheit - 32)           "Celsius
                        0.556
                                            IX

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                                     Acknowledgments
This report was prepared under the direction of Mr. David Carson, the Environmental Protection Agency Super-
fund Innovative Technology Evaluation Program project manager at EPA's National Risk Management Resource
Laboratory in Cincinnati, Ohio.  Contributors and reviewers for this report were Dr. Ronald Terrel of Terrel
Research in Edmonds, Washington; Mr. Karl Yost of Wilder Construction Company in Everett, Washington; and
Kenneth Grzybowski of PRI Asphalt Technologies, Inc., in Tampa, Florida. Gregory Jackson of Dover Air Force
Base and Mike Peterson of Waste Management, Inc., provided invaluable field support during the demonstrations.

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                                       Executive Summary
Hazardous waste has been contained at several Resource
Conservation and Recovery Act (RCRA) and Superfund
sites around the country for the past 20 years using clay
and geosynthetic covers. These covers often do not allow
site reuse for  industrial or commercial development.
With the growing need to redevelop Brownfields  sites
(contaminated  sites in urban areas),  covers  that allow
industrial or commercial use  are preferred.   Wilder
Construction Company (WCC) of Everett, Washington, has
developed the MatCon™ (Modified Asphalt Technology
for Waste Containment) technology for covers, which
allows site reuse at hazardous waste sites. In 1998, WCC
requested the  U.S. Environmental Protection  Agency
(EPA) to evaluate this technology under the  Superfund
Innovative  Technology  Evaluation (SITE) Program at
Dover Air Force Base (DAFB) in Dover, Delaware.  In
1999, the evaluation was expanded to also include the Tri-
County Landfill (TCL) Superfund site in Elgin, Illinois.
This Innovative Technology Evaluation Report (ITER)
presents the details of the evaluation and the performance
data obtained at the DAFB and TCL sites. The following
sub-sections describe the sites and evaluation procedures,
list objectives  and summarize associated results, and
provide conclusions.

Dover Air Force Base Site

The  Matcon™ cover installed at the DAFB  covered
an area  of  124 x 220 feet  (ft).  The installation was
completed in April 1999, and samples were collected
in August 1999. The Matcon™ cover at the DAFB site
consisted of three, hydraulically independent sections;
Section I was a 12-inch-thick section (one 4-inch-thick
open graded MatCon™ layer serving as a drainage layer
between two 4-inch-thick layers of MatCon™; Section II
was a 4-inch-thick MatCon™ layer; and Section III was
a 4-inch-thick layer of conventional asphalt.  Perforated
high density polyethylene  (HOPE) pipes were placed
in the open graded MatCon™ layer within Section I to
convey water infiltrating the MatCon™ cover to a sump
at the edge of the cover.

Several  cores and  slab samples of the MatCon™ and
conventional asphalt covers were collected from this site
to compare the following laboratory-measured properties
of MatCon™ with conventional asphalt.

 •  Hydraulic permeability

 •  Flexural properties

 •  Joint integrity

 •  Load capacity

 •  Tensile strength

 •  Thermal crack resistence

 •  Permeability after 30 and 60 days  of accelerated
    weathering

 •  Fuel resistance

 •  Void space

 •  Aggregate properties

 •  Hydraulic transmissivity of the drainage layer (open
    graded MatCon™)

In  addition,  field  permeability  was  calculated by
measuring the infiltration through the MatCon™ cover
during precipitation events. Field permeability tests were
performed on Section I at the DAFB site.

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Tri-County Landfill Site

A 3.6-acre (14,569-square meter [m2]) MatCon™ cover
was installed at the TCL site in November 1999 adjacent
to the recycling facilities of Waste Management, Inc. The
thickness of the MatCon™ cover was 4 inches (10 cm) over
most of the area except the lysimeter test section (30 feet
by 80 feet [9.2 by 24.2 m]), which consisted of 2 inches
(5 cm) of conventional asphalt overlain by 40-millimeter-
thick geomembrane and geotextile, 6 inches (15 cm) of
coarse aggregate, and 4 inches (10 cm) of MatCon™ cover.
A 3-inch-diameter (7.6-cm) perforated HDPE drainage
pipe  was placed in the 6-inch-thick (15-cm) aggregate
section to convey the infiltration into the MatCon™ cover
to a sump at the edge of the cover. This variation in the
drainage layer design from what was used at the DAFB
site was requested by the U.S. Army Corps of Engineers,
the supervisor of the remediation at the TCL site.

Laboratory samples  were  collected from locations
away from the lysimeter test section.  These samples
were tested for void space, aggregate properties, and
hydraulic permeability. In April 2000, further sampling
was completed at an area of the cover where a crack was
observed.  WCC determined that the crack was due to a
cold joint formed because of poor workmanship during
the November installation (see  Section 4.1.3.2).  The
crack was repaired, and a procedure for construction of
cold joints was developed (Appendix B).

Field permeability was also calculated at the TCL site by
measuring the infiltration through the MatCon™ cover
during precipitation events and constant-exposure ponding
tests. Field permeability tests were  performed  on the
demonstration portion of the cover at this site.

Objectives and  Results

The technology demonstration objectives and results are
described below.

 • Primary objective  1:  Determine if  the MatCon™
   cover exhibits a field permeability of less than the
   RCRA Subtitle C  requirement of 10~7 centimeters
   per second (cm/sec).  At the DAFB site, the  field
   permeability  values of the MatCon™ cover varied
   from 1.28 x 10~7 cm/sec to 1.31 x 10~8 cm/sec.  A 6-
   hour ponding test indicated a permeability of 1.25 x
    10"8 cm/sec.

   At the TCL site, the field permeability  of the
   MatCon™ cover varied from 3.36 x 10~9 cm/sec to
   5.15 x 10'10 cm/sec based on drainage measurements
during precipitation events. A 48-hour ponding test
on the cover yielded a permeability value of 5.0 x
10"8 cm/sec.

Primary  objective  2:  Compare the  laboratory-
measured permeability and flexural properties of the
MatCon™ cover with the conventional asphalt cover
at the DAFB site.  At the DAFB site, the laboratory
permeability of the MatCon™ cover was less than
1.0 x  10"8 cm/sec,  whereas the permeability of
conventional asphalt varied from 1.04 to 2.75 x 10~4
cm/sec. At the TCL site, the laboratory permeability
of the MatCon™ cores was less than 1.0 x 10~8 cm/sec,
except for the cores obtained on the crack described
above, which had a permeability of 3.5 6 x 10~5 cm/sec.
The cores obtained on the crack had a void content
of 8.2 percent, compared to less than 3 percent for
properly installed  MatCon.™

A 36-inch-long beam of MatCon™ asphalt sustained
20.41 millimeter (mm) of deflection without cracking,
whereas a conventional asphalt beam cracked at 7 to
10 mm deflection. The conventional asphalt beam
showed 3-mm wide, 2.5-cm long cracks at about 25
mm of deflection.

Secondary objective 1:  Compare  other laboratory-
measured physical properties of the MatCon™ cover
and the conventional asphalt cover at the DAFB
site.  The resilient modulus of the MatCon™ cover
was 2,048 megapascals (Mpa), compared to 3,200
Mpa  for the conventional asphalt cover at cold
temperatures (-20 degrees C).  This reduced modulus
suggests  that MatCon™ is more  flexible and  less
susceptible to cracking at cold temperatures.

The tensile strength of the MatCon™ cover was 3.551
Mpa, compared to 2.579 Mpa for the conventional
asphalt cover.  The fracture temperature of the
MatCon™ cover was 4.3 degrees Celsius lower than
the conventional asphalt cover.

The MatCon™ cover had a 37 percent higher fracture
strength than conventional asphalt.

The  accelerated  aging tests indicated that  the
MatCon™  cover  was  essentially  unaffected by
exposure to ultraviolet light,  maintaining the same
PG rating  after 60 days of aging, whereas  the
conventional asphalt binder lost both high  and  low
temperature performance on exposure to ultraviolet
light. However, the permeability of the MatCon™
cover increased by  an  average  of two orders of
magnitude after accelerated aging (2.2 x 10~6 cm/sec).
The permeability of the conventional cover remained
generally unchanged (3.15 x 10~4 cm/sec).

Exposure to cyclic water sprays  for 60 days  had
a minimal  effect  on the  binder properties of the
MatCon™ cover, and the MatCon™ binder had wider
performance grade as compared to the conventional
asphalt binder.

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    Exposure to fuel degraded the top 1.5 cm (out of a
    total of 10-cm thickness) of the MatCon,™ cover,
    whereas the conventional asphalt cover showed 5.5
    cm degradation (out of a total of 10-cm thickness).

 •  Secondary objective 2: Determine whether extreme
    weather conditions or vehicle loads affect the field
    performance of the MatCon™ cover. The MatCon™
    surface performed well under extreme cold weather
    conditions and significant vehicle loads at the Tri-
    County Landfill site.  The  MatCon™ surface was
    used  for  parking recycling vehicles and garbage
    trucks from the day the cover was installed.

 •  Secondary  objective 3: Estimate  a cumulative
    hydrologic balance for the MatCon™ cover over
    the period of the demonstration at the DAFB site.
    A hydrologic balance could not be performed at the
    DAFB site.

 •  Secondary  objective 4:  Estimate the  cost  for
    constructing the MatCon™ cover and maintaining
    the cover for the duration of the demonstration.  The
    cost of MatCon™ cover installation is estimated to
    be $124,000 to $140,000 per acre including subgrade
    preparations. This is comparable to the cost of RCRA
    Subtitle D covers and less than the cost per acre of
    RCRA Subtitle C covers, which range from $150,000
    to $300,000, depending on the local availability of
    appropriate cover materials  (Dwyer 1998).

Conclusions

The demonstrations at the DAFB and TCL sites indicate
that the MatCon™ cover is suitable  for use as a low
permeability cover at hazardous waste sites. Based on the
results of the test plots, the permeability of the MatCon™
cover was lower than or equal to the 1.0 x 10~7 cm/sec
requirement for hazardous waste landfill covers.  The
demonstrated MatCon™ covers performed well under
extreme cold weather conditions and under use as a staging
area for heavy vehicles.

The  MatCon™ cover permits  site reuse.  The main
limitations of the technology are that it cannot be used
at sites having slopes greater than 3 to 1 or at sites that
cannot provide a firm and unyielding subgrade to support
the paving equipment used to install the cover.

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                                             Section 1
                                           Introduction
This section briefly describes the SITE Program and
SITE reports;  states the purpose and  organization  of
this ITER; provides background information regarding
the development of the MatCon™ process technology;
identifies wastes to which this technology may be applied;
and  provides a list of key contacts who  can  supply
information  about  the  technology and demonstration
site.

1.1    Description of SITE Program and Re-
       ports

This section briefly describes the purpose, history, and
goals of the SITE Program, and the reports that document
SITE demonstration results.

7.7.7  Purpose, History, and Goals of the SITE
       Program

The primary purpose of the SITE Program is to advance
the development and demonstration, and thereby establish
the commercial  availability, of  innovative treatment
technologies applicable to Superfund and other hazardous
waste sites.  The SITE Program was established by the
EPA Office of Solid Waste  and Emergency Response
(OSWER) and Office of Research and Development
(ORD) in response to the Superfund Amendments and
Reauthorization Act of 1986 (SARA), which recognized
the need for an alternative or  innovative treatment
technology research and demonstration program.  The
SITE Program is  administered  by ORD's  National
Risk Management  Resource  Laboratory  (NRMRL).
The  overall goal of the SITE Program is to carry out a
program of research, evaluation, testing, development,
and demonstration of alternative or innovative treatment
technologies that may be used in response actions  to
achieve long-term protection of human health and welfare
and the environment.
The SITE Program includes the following elements:

 • The MMT Program evaluates innovative technologies
   that sample, detect, monitor, or measure hazardous
   and toxic substances.   These  technologies  are
   expected  to provide better, faster, or  more cost-
   effective methods for producing real-time data during
   site characterization and remediation studies than do
   conventional technologies.

 • The Remediation  Technology Program conducts
   demonstrations of innovative treatment technologies
   to provide reliable performance, cost, and applicability
   data for site cleanups.

 • The Technology Transfer  Program provides and
   disseminates  technical information  in the form
   of updates,  brochures,  and  other  publications
   that promote the SITE Program and participating
   technologies. The Technology Transfer Program also
   offers technical assistance, training, and workshops
   to support the technologies. A significant number of
   these activities are  performed by EPA's Technology
   Innovation Office.

Innovative technologies chosen for a SITE demonstration
must be pilot- or full-scale applications and must offer some
advantage over conventional technologies.  To produce
useful  and reliable data, demonstrations are conducted
at actual hazardous waste sites or under conditions that
closely simulate actual waste site conditions.

Data collected during the  demonstration are used to
assess the performance of the technology, the potential
need for pretreatment and post-treatment processing of
the treated waste, the types of wastes and media that can
be treated by the technology, potential treatment system
operating problems, and approximate capital and operating
costs.  Demonstration data can also provide  insight into
a technology's long-term  operation  and maintenance
(O&M) costs  and long-term application risks.

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Under  each  SITE  demonstration,   a  technology's
performance in treating an individual waste at a particular
site is evaluated. Successful demonstration of a technology
at one site does not ensure its successes  at other sites.
Data  obtained  from the demonstration may  require
extrapolation to estimate a range of operating conditions
over which the technology performs satisfactorily.  Any
extrapolation of demonstration data also should be based
on other information about the technology, such as case
study information.

Cooperative  arrangements between EPA, the site owner,
and the  technology developer establish responsibilities
for conducting the demonstration and evaluating the
technology.  EPA is  responsible  for project planning,
sampling and  analysis,  quality assurance  and  quality
control (QA/QC), preparing reports, and  disseminating
information.  The site owner is responsible fortransporting
and disposing of treated waste materials and site logistics.
The technology developer is responsible for demonstrating
the technology at the selected site and is expected to
pay any costs for transport, operations, and removal of
equipment.

Implementation of the  SITE Program  is a significant,
ongoing effort involving ORD, OSWER, various EPA
regions,  and  private  business  concerns, including
technology developers and parties responsible for site
remediation. The technology selection process and the
Demonstration Program together provide a means to
perform objective and carefully  controlled testing of
field-ready technologies. Each year, the SITE Program
sponsors about 10 technology demonstrations. This ITER
was prepared under the SITE Demonstration Program.

7.7.2  Documentation of Site Demonstration
        Results

The  results  of each  SITE demonstration  are usually
reported in four documents: (1) a Demonstration Bulletin,
(2) a Technology Capsule, (3) a Technology Evaluation
Report (TER), and (4) the ITER.  The Demonstration
Bulletin provides atwo-page description of the technology
and project history, notification that the demonstration was
completed, and highlights of the demonstration results.
The Technology Capsule provides a brief description of
the project and an overview of the demonstration results
and conclusions.

The purpose  of the TER is to consolidate all information
and records acquired during the demonstration. The TER
data tables and graphs summarize test results in terms of
whether project objectives and applicable or relevant and
appropriate requirements (ARAR) were met.  The tables
also summarize QA/QC data in comparison to data quality
objectives.  The TER is not formally published by EPA.
Instead, a copy is retained by the EPA project manager
as a reference for responding to public inquiries and for
record-keeping purposes.  The purpose and organization
of the ITER are discussed in Section 1.2.

1.2   Purpose  and Organization  of the ITER

Information presented in the ITER is  intended to assist
decision-makers  in evaluating specific technologies for
a particular cleanup situation.  The ITER represents a
critical step in the development and commercialization
of a technology demonstrated under the SITE Program.
The ITER discusses the effectiveness and applicability
of the technology and analyses costs associated with its
application. The technology's effectiveness is evaluated
based on data collected during the SITE demonstration
and from other case  studies.  The applicability of the
technology is  discussed  in  terms  of waste and  site
characteristics that could affect technology performance,
material handling requirements, technology limitations,
and other factors.

This  ITER consists of  six sections,  including  this
introduction. Sections 2 through 6 and their contents are
summarized below.

 •  Section 2,  Treatment Applications  Analysis,
    discusses information relevant to the application
    of the MatCon™ process technology,  including an
    assessment of the technology related to the nine
    feasibility study  evaluation criteria, potentially
    applicable  environmental  regulations, and  the
    operability and limitations of the technology.

 •  Section 3, Economic Analysis, summarizes the actual
    costs, by cost category,  associated with  using the
    MatCon™ process technology,  variables that may
    affect costs at other sites, and conclusions derived
    from the economic analysis.

 •  Section 4, Technology Effectiveness, presents
    information relevant to the design and implementation
    of the technology. It also presents an overview of
    the SITE demonstration objectives, documents the
    demonstration procedures, and  summarizes  the
    results  and conclusions of the demonstration.

 •  Section 5, Technology Status,  summarizes  the
    developmental status of the MatCon™ process
    technology.

 •  Section 6,  References, lists the references used to
    prepare this ITER.

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In addition to these sections, this ITERhas two appendices:
Appendix A, Vendor's Claims for the Technology and
Appendix B, Vendor's Discussion of MatCon™  Cold
Joints.

1.3    Matcon™Technology Description

MatCon™,  an  abbreviation  for  Modified  Asphalt
Technology for Waste Containment,  is a technology
developed by Wilder Construction Company (WCC)
to contain hazardous wastes  at RCRA and  Superfund
sites. The MatCon™ asphalt mix contains high quality,
specifically sized  mineral  aggregate  and a highly
modified proprietary binder using additives beneficial to
environmental applications. The binder content is about
7 percent, and the air void content is less than 3 percent
compared to an air void content of about  8 percent for
conventional asphalt mixes.

The MatCon™ mix, when properly installed using high
quality paving techniques, offers unique advantages over
conventional asphalt. The permeability of MatCon™ is
less than 10~7 cm/sec, and it offers greater resilience and
longevity than conventional asphalt. The first MatCon™
cover was installed in Ferndale, Washington in  1989.

The advantages claimed by WCC for the  MatCon™
technology include the following.

 •  MatCon™ does not crack like compacted clay and
    is not subject to damage under ultraviolet  light
    exposure

 •  MatCon™ resists corrosion  and conforms  well
    to small  differential  settlement  of underlying
    materials

 •  MatCon™ cover thicknesses vary from 4 to 12 inches
    (10 to 30.5  cm) compared to conventional RCRA
    covers, which are over 3 feet (0.9 meter) thick

 •  MatCon™ can be rapidly installed on a prepared
    subgrade (about 1.5 acres per day [0.6 hectares per
    day]) and used immediately after installation

 •  A large number of asphalt paving contractors in
    the country  have the skill, equipment, and trained
    personnel  to install MatCon™ according to WCC
    specifications

During a typical  MatCon™ cover installation, WCC
brings its proprietary binder to  a local asphalt plant
and provides supervision for hot mix preparation.  The
MatCon™ asphalt mix is then placed as a cover under
strict assurance QC specifications provided by WCC. A
4-inch thick (10-cm), highly permeable (about 1 x 10~2
cm/sec) drainage layer made of open graded MatCon™
is sandwiched between two 4-inch thick (10-cm) layers
of impermeable MatCon™ mix to create a double lined
version of the system.

1.4     Key Contacts

Additional information on the MatCon™ covertechnology
is available from the following sources.

David Carson
U.S. Environmental Protection Agency
Office of Research and Development
26 West Martin Luther King Drive
Cincinnati,  OH 45268
Telephone:  (513) 569-7527
FAX: (513) 569-7879
email: carson.david@epa.gov

Karl Yost or Jerry Thayer
Wilder Construction Company
1525 E. Marine View Drive
Everett, WA 98201
Telephone:  (425) 551-3100
FAX: (425) 551-3116
email: karlyost@wilderconstruction.com
jerrytha@wilderconstruction.com

Gregory D. Jackson, P.E. (DAFB site contact)
Environmental Engineer
436 CES/CEV
600 Chevron Avenue
Dover Air Force Base, DE 19902-6600
Telephone:  (302) 677-6846
FAX: (302) 677-6837
email: gregory.jackson@dover.af.mil

Michael Peterson (TCL site contact)
Waste Management, Inc.
West 124 North 9355 Boundary Rd.
Menominee Falls, WI 53051
Telephone:  (262) 253-8626, ext. 115
FAX: (262) 255-3798
email: mpeterson@wastemanagement.com

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                                             Section 2
                               Technology Applications Analysis
This section describes the SITE demonstration objectives
and  evaluation  design  conclusions,  including  the
demonstration results, factors influencing the effectiveness
of the  MatCon™ technology, personnel requirements,
potential regulatory requirements, and appropriate waste
and site conditions.  The vendor's claims regarding the
applicability and performance of the technology are
included in Appendix A. The technology's applicability
is based on the results of two demonstrations conducted
underthe SITE Program. The SITE demonstration results
are presented in detail in the TER.

2.1     SITE  Demonstration Objectives  and
        Conclusions

The  SITE demonstrations were conducted at DAFB in
Dover, Delaware (Figure 2-1) and TCL in Elgin, Illinois
(Figures 2-2 and 2-3), where contaminated site capping
was in progress. WCC (1998) provides details of WCC's
demonstration program application for the DAFB site.
The objectives of the two demonstrations are described
below.

Each of the project objectives is listed below and identified
as either primary (P) or secondary (S).  Primary obj ectives
were considered critical for the technology evaluation,
and  secondary objectives provided additional useful
information.   For each objective, a brief description
of the  experimental approach is given.  Details of the
experimental approach  and results are given in Section
4.0.

Two primary objectives were identified:

PI—Determine if the MatCon™ cover exhibits a field
permeability of less than the RCRA Subtitle C requirement
of 10~7  centimeters per second (cm/sec) (CFR, 2002).
To estimate the field permeability of the MatCon™ cover,
the volume of infiltration during individual rainfall events
was measured during the demonstration period at each
of the two sites.

Using  Darcy's Law,  the measured  infiltration  rates
were  converted  into estimates  of field permeability,
and these estimates were compared to the regulatory
requirement.   Field permeability  was calculated  as
the hydraulic conductivity of the  installed cover, and
reported  in the  units  cm/sec.   Although the  terms
permeabilityand  hydraulic conductivity are  typically
defined separately,  the terms are considered to  be
interchangeable for the purpose of discussion of this
demonstration.

P2—Compare  the  laboratory-measured permeability
andflexural properties  of the MatCon™ cover and the
conventional asphalt cover at the DAFB site.

The vendor claims that the MatCon™ cover is less
permeable  and has superior flexural  properties  when
compared to conventional asphalt.  To  test these claims,
laboratory tests that evaluate the two properties  were
conducted on both  MatCon™ and conventional asphalt
samples from the DAFB site.  Results for each parameter
were then compared to determine whether the MatCon™
cover appears to be superior to conventional asphalt for
these two critical parameters.

Four secondary objectives were identified:

SI—Compare  other   laboratory-measured  physical
properties of the MatCon™ cover and the conventional
asphalt cover at the DAFB site.

The vendor makes  no specific claim for the superiority
of MatCon™ to  conventional asphalt with respect to
physical parameters, other than permeability and flexural
properties.   However,  differences in  other physical
properties that can be measured in the laboratory may be
of interest to potential users. Therefore, samples of both
                                                  7

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                                                                                      Dover
                                                                                     Air Force
                                                                                       Base
                                                                   Dover
                                                                   Family
                                                                  Housing
                                                                   Annex
Figure 2-1. Location of Dover Air Force Base.

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1/2
                                                      SCALE  1:24000
                                                              0
                                                                                                         1 MILE
                          1000
                                           1000    2000     3000    4000     SOOO    6000  7000 FEET
       LEGEND
             SCALE:  1" -  2,000'
              ^^^m  Primary Highway
              	  Light-Duty Road
               =: =  Unimproved  Rood
              —<—i-  Railroad
       NOTE' All pink shading represents
               residential areas.

   SOURCE: MODIFIED FROM USGS,
   	GENEVA, ILLINOIS, QUADRANGLE, 1993
Quad

/I
ILLINOIS
\J

rangle Location
WATCON™ TECHNOLOGY EVALUATION
TRI-COUNTY LANDFILL
ELGIN, ILLINOIS
FIGURE 2-2
SITE LOCATION
G3 TetraTech EM Inc.
Figure 2-2. Site location, Tri-County Landfill, Elgin, Illinois.

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   SOURCE: Modified from Montgomery Watson 1999
                                             150'     0	ISO'      300"
                                                 SCALE:  1" = 300'
Figure 2-3. Site layout, Tri-County Landfill, Elgin, Illinois.

                                                              10

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the MatCon™ cover and the conventional cover were
collected from the DAFB site and analyzed for various
parameters pertinent to the physical performance of the
cover.  Results for each parameter were then compared
to determine potential significant differences between the
two types of covers.

S2—Determine whether extreme weather conditions or
vehicle loads affect the field performance of the MatCon™
cover.

To evaluate this objective, the MatCon™ covers at both
sites were inspected periodically in the field, particularly
following periods of extreme cold or other adverse weather
conditions, to  assess the development of potential cracks
or surface defects. These field inspections were used to
evaluate the effects of extreme weather or vehicle  loads
since the previous inspection. General information on use
of the covers and on recent weather events was collected
from the  site owners and evaluated against any surface
defects noted  in the field inspections. The TCL site in
Elgin, Illinois encountered much colder temperatures than
the DAFB site in Dover, Delaware. As a result, data on
the impacts of extreme cold were observed only at the
TCL site.

S3—Estimate a cumulative hydrologic balance for the
MatCon™ cover over the period of the demonstration at
the DAFB site.

A hydrologic balance for the cover system was estimated
at the DAFB site. The hydrologic balance was based on
cumulative precipitation, totalized surface runoff, and
subsurface drainage during the demonstration period.

S4—Estimate  the cost for constructing the MatCon™
cover and maintaining the cover for the duration of the
demonstration.

The capital and operating costs for the MatCon™ cover
technology, as demonstrated at both the DAFB and TCL
sites, were estimated  based on the following 12 cost
categories: site and facility preparation cost; permitting
and  regulatory costs;  equipment  costs;  labor  costs;
consumables and supplies costs; startup and fixed costs;
utilities costs; effluent treatment and  disposal  costs;
residual and waste shipping, handling, and transportation
costs;  analytical costs;  facility modification, repair,
and replacement costs; and site restoration costs.  Cost
information obtained from WCC was reviewed by Tetra
Tech in preparing the cost estimate.
2.2    Feasibility Study Evaluation Criteria

The MatCon™ technology performance demonstrated at
the DAFB and TCL sites satisfied the nine criteria used
for determining its feasibility for Superfund sites. Table
2-1 summarizes the performance of the technology with
respect to each of the nine feasibility criteria for application
at Superfund sites.   Further analysis of  MatCon™
performance is provided in the following sections.

2.2.1  Overall Protection of Human  Health
       and the Environment

Hazardous waste landfills may adversely impact human
health  and the environment  by producing  airborne
contamination and hazardous leachate.  The MatCon™
cover provides complete containment of the hazardous
waste and limits these adverse impacts.  It has been
successfully implemented at the  DAFB and TCL sites
and at McClelland Air Force Base in California.

2.2.2  Compliance with Applicable or Rele-
       vant and Approriate Requirements

The primary ARAR for source control at hazardous waste
landfills is the RCRA Subtitle C permeability requirement
of 10'7 cm/sec  for hazardous waste landfills.  The
demonstrations at the DAFB and  TCL sites have shown
that the permeability of the MatCon™ cover is less than
10~7 cm/sec. Therefore, the MatCon™technology satisfies
the ARARs for hazardous waste landfills.

2.2.3  Long-Term  Effectiveness  and
       Permanence

Testing of various physical properties, such as fracture
strength and resistance to accelerated weathering, has
indicated that the MatCon™ cover is more durable than
conventional asphalt, and can be a permanent containment
system requiring limited maintenance. WCC installed the
first MatCon™ cover over incinerator ash in Ferndale,
Washington in 1989. This site was not evaluated as part
of this  demonstration;  however, WCC claims that this
cover has maintained a 10~8 cm/sec permeability over
the past 12 years, even though the cover has been used
as an active work surface for heavy equipment operation
and material staging. The cover has required little or no
maintenance over this long period, demonstrating the long-
term effectiveness of the MatCon™ cover. The MatCon™
mix is made of natural and recyclable materials (aggregates
and modified asphalt)  that are used extensively in the
                                                 11

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Table 2-1. Superfund Feasibility Evaluation Criteria for the MatCon™ Technology
    Criterion
Discussion
    Overall protection of human health
    and the environment
    Compliance with applicable or
    relevant and appropriate
    requirements (ARAR)


    Long-term effectiveness and
    permanence
    Reduction of toxicity, mobility, or
    volume through treatment


    Short-term effectiveness
    Implementability
    Cost
    State acceptance
    Community acceptance
1.  The MatCon™ technology is expected to protect human health
   by containing the hazardous waste. It affords environmental
   protection by preventing the formation of leachate at
   hazardous waste landfills.

2.  The MatCon™ technology complies with the RCRA Subtitle
   C permeability requirement of 10-7 cm/sec for hazardous
   waste landfill covers. It also  complies with state and local
   ARARs.

3.  Testing of various physical properties, such as fracture
   strength and resistance to accelerated weathering, has
   indicated that the MatCon™ cover can be a permanent
   containment system requiring limited maintenance. The
   technology uses natural and  recyclable materials (aggregates
   and modified asphalt) that are used extensively in the
   construction industry.

4.  The technology reduces the mobility of hazardous waste by
   reducing infiltration at  landfill sites and does not involve waste
   treatment; therefore, this criterion is satisfied.

5.  A MatCon™ cover can be constructed within a few weeks and
   can reduce infiltration immediately following installation. The
   technology can be implemented expeditiously and is effective
   in preventing water infiltration into the waste.

6.  The technology is readily implementable since hot mix plants
   are available in all parts of the country. Standard, readily
   available paving equipment can be used

7.  The cost is often less than RCRA Subtitle C clay and
   geosynthetic covers. Potential beneficial reuse of the site is a
   very attractive feature of the technology.

8.  The technology has been approved in several states, including
   Delaware, Illinois, Texas, California, Florida, Washington,
   and others because of the redevelopment possibilities with a
   MatCon™ cover.

9.  Community acceptance of the technology is likely because of
   the redevelopment possibilities with a MatCon™ cover.
                                                       12

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construction industry, which should result in permanence
of the MatCon™ cover.

2.2.4 Reduction  of Toxicity,  Mobility,  or
       Volume Through Treatment

The MatCon™ technology does not involve treatment
of waste or contaminated material; therefore, it cannot
reduce toxicity or volume through treatment.  However,
the MatCon™ cover reduces the mobility of contaminants
in the landfill by minimizing  entry of water into the
waste; as a result, leachate production  and migration is
minimized.

2.2.5 Short-Term Effectiveness

Depending on the size of the cover required, the MatCon™
technology can be installed in as little as one day, to within
a few weeks and immediately prevents entry of water into
the waste. Therefore, the MatCon™technology provides
short-term effectiveness  by minimizing formation of
leachate.

2.2.5 Implementability

The ease of implementation is an attractive feature of the
MatCon™ technology. The proprietary  binder is shipped
to the hot mix plant nearest to the site, and the mix is
prepared under WCC supervision.  Paving  equipment
available  from local paving  contractors can  be used to
install the MatCon™ cover in a few weeks.

2.2.7 Cost

The installation  cost varies from $124,000 to $140,000
per acre and is less than that for RCRA Subtitle C clay
and geosynthetic covers.  In addition, the time required
to install the MatCon™ cover is significantly less than
that for clay and geosynthetic covers.   Mobilization
and demobilization costs are also less than for clay and
geosynthetic covers.

2.2.8 State Acceptance

MatCon™ has been  included in state-approved design
specifications of landfill covers installed at sites in the
states  of California, Colorado, Delaware, Florida, Illinois,
Kentucky, New Mexico, Texas, and Washington. Approval
is based on the  low  permeability of the cover and the
redevelopment or reuse possibilities for the  MatCon™
cover surface.
2.2.9  Community Acceptance

The  states  mentioned in Section  2.2.8 approved the
MatCon™  cover  because  of community acceptance
for site redevelopment at closed landfills. The ease of
maintenance for the MatCon™ cover is also attractive
to communities.

2.3    Technology Applicability

The MatCon™ technology can be used  as a final cover
at many hazardous waste sites where a firm foundation
is available or can be constructed.  The MatCon™ cover
offers a major advantage over RCRA Subtitle C  or D
covers when site reuse is planned.  The following are a
few of the site reuse possibilities:

 • Parking or staging area for equipment and vehicles

 • Material processing and treatment pads

 • Petroleum hydrocarbon-resistant surface for fueling
   operations

 • Light industrial manufacturing and warehousing

 • Sports facilities, such as tennis courts and running
   tracks

The MatCon™ cover at the TCL site has been used as a
staging area for garbage trucks and recycling vehicles since
the day it was installed. In addition, a large fuel oil tank
placed on the cover is used for fueling the vehicles.

The demonstrations  at the DAFB and TCL sites  have
proven the  applicability of the technology in wet and
cold  climates.  An additional demonstration is planned
in 2003 at Kirtland Air Force Base in Albuquerque, New
Mexico.

2.4    Limitations of theTechnology

The limitations of the technology can be grouped under
three categories: site characteristics, quality control, and
extent of site reuse.  These limitations are discussed in
the following subsections.

2.4.1  Site Characteristics

MatCon™ cover applications require the following site
conditions:

 • The subgrade  to receive the MatCon™ cover must
   be firm and unyielding to support compaction of the
   MatCon™ asphalt during construction.
                                                 13

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 •   The subgrade to receive the MatCon™ cover must
    have slopes of less than 3:1 (heightvolume) for the
    safe use of compacting and paving equipment during
    installation.

 •   The subgrade to receive MatCon™ must have a slope
    of greater than 1.5 percent to facilitate drainage and
    minimize surface water ponding.

 •   The subgrade must be constructed to a  grading
    tolerance of plus or minus 0.5 inch (1.3 cm).

2.4.2  Quality Control

The MatCon™ cover has to be prepared and installed under
strict quality assurance (QA)  procedures in accordance
with WCC's specifications and construction QAprogram.
The MatCon™ mix must be produced in a local hot mix
plant under the WCC QA program.

2.4.3  Site Reuse

Though heavy surface use on a MatCon™  cover  is
possible, heavy  container  stacking,  extraordinarily
heavy or repeated  loads, sharp point source loading,
misuse,  or use  of heavy tracked equipment might
compromise its integrity. Such heavy surface uses can be
accommodated through customized designs, formulations,
and construction  methods.  WCC prepares site specific
Operations and Maintenance Plans for each installation
and the potential future surface uses.
                                                 14

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                                              Section 3
                                        Economic Analysis
The primary purpose  of this  economic analysis is to
estimate costs of utilizing the MatCon™ cover to provide
source control at hazardous waste sites.  Site-specific
factors affecting cost, the basis of the economic analysis,
cost categories, and cost per acre of MatCon™ installation
are described below.

Costs have been divided into four categories that are
applicable to this technology. The four categories are:

 •  Site preparation

 • Permitting and regulatory

 • Labor

 •  Supplies and consumables

Table 3-1  shows the estimated costs for preparing the
MatCon™ mix and installing the cover on one acre.

The following eight categories typically associated with
cleanup activities at Superfund and RCRA-corrective
action sites  are  not  applicable  to  the MatCon™
technology.

 • Capital equipment

 •  Startup costs

 • Demobilization

 • Utility costs

 • Effluent treatment and disposal

 • Residuals and waste shipping and handling

 • Equipment maintenance and modifications

 • Analytical and monitoring costs
MatCon™  is a  containment system technology, not
a treatment technology that reduces waste  toxicity.
The  equipment  used  to  install the  MatCon™ cover
is  conventional  paving equipment,  and this  task is
subcontracted by the project owner, engineer, or WCC
to  a qualified local paving contractor.   Therefore,  no
startup, demobilization, or capital equipment costs are
involved. The cost of equipment (capital and operating)
for a MatCon™ installation cannot be separated out from
the total equipment costs of the paving contractor and is
included in the labor overhead under labor costs.

MatCon™ cover installation does not require separate
utility  costs, and the  fuel required to run the paving
equipment is included in the labor costs charged by the
paving contractor. The technology does not treat waste;
therefore, no cost is associated with effluent treatment
and disposal, residual and waste shipping and handling,
or analytical  and  monitoring.  The  vendor-specified
construction quality control (CQC) testing is included in
the labor costs.

3.1     Site-Specific Factors Affecting Costs

Two site-specific factors impact the cost of MatCon™
cover installation. These are (1) physical site conditions
related to the subgrade and (2)  geographical location,
which  affects transportation costs for the hot mix and
paving contractor costs.  The size of the paved area did
not have much impact on the cost per acre for MatCon™
installation.

The variation in  costs  due to physical conditions at the
site is demonstrated in costs incurred  at the DAFB and
TCL sites. The subgrade at the TCL site was constructed
over municipal waste and required 8 inches (20 cm) of
crushed rock, compared to 6 inches (15 cm) at the DAFB
site (a  difference of $3,000 per acre). Labor costs and
cost of supplies were also less at DAFB compared to the
                                                  15

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Table 3-1. Estimated Costs Associated With MatCon™ Installation

                                                                    Estimated Cost Per
            Cost Category                                                  Acre
                                                                         (Dollars)
            Site preparation                                           7,000 to 10,000
            Permitting and regulatory                                       2,000
            Startup                                                          0
            Labor                                                    35,000 to 45,000
            Supply and consumables                                 80,000 to 83,000
            Utilities                                                          0
            Effluent treatment and disposal                                   0
            Residual and waste shipping and handling                         0
            Analytical and monitoring                                        0
            Maintenance and modifications                                   0
            Demobilization                                                  0
            Total cost per acre                                       124,000 to 140,000
TCL site because of site proximity to the local asphalt   •   A qualified paving contractor is available in the
plant (a difference of $12,000 per acre).                     project area.
The costs presented in this analysis are based on conditions   '                ^
at the DAFB and TCL sites.  Because these costs were  A dlscusslon of the four cost categories applicable to the
not independently verified at the sites, all costs presented  MatCon™ cover installation and the elements associated
in this section were provided by WCC.                  with each category is provided below.  These costs are
                                                    based on the costs per acre experienced by WCC at the
3.2    Basis of Economic Analysis              DAFB and TCL Sltes
The following assumptions were made for this economic   _,  _, „   _.   „
analysis                                             3 3 1   S,te Preparat.on
    _    .   .  ,      ,   . , .   „„   .,   ,_„ , .,          The costs associated with site preparation include grading
 •  Ine site is located within 20 miles (32 kilometers  .,     ,,               <±    .      .•    ?^      •   i
    [km]) of the asphalt plant.                         the surface to remove  soft sPots' creatlon of the recluired
                                                    slope, and placing crushed rock subgrade to support the
 •  Suitable access roads are available.                 MatCon™ cover installation.
 •  The  site has relatively firm  soils with  a bearing  Sites that require a substantial amount of fill or reinforcing
    capacity of about 1 ton per square foot.              .           -,    .     ,  ,,       «    u       -nu
                                                    to  repair sort spots and  form a firm  base will  nave
 •  The site is relatively flat and dry.                   significantly higher site preparation costs. At the  TCL
                                                    site, soils overlying municipal waste could be prepared by

                                                  16

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placing about 8 inches of crushed rock to form a suitable
subgrade.  Costs at the DAFB site for site preparation
were somewhat lower because of a firmer base.  The site
preparation costs ranged from $7,000to $10,000 per acre.
Site preparation is typically performed by a local civil
grading contractor.

3.3.2 Permitting and Regulatory Costs
These costs are dependent on the type of waste and the
environmental laws, regulations, and ordinances of federal,
state, and local jurisdictions. Because installation of the
MatCon™ cover provides source control and facilitates
site reuse, it is not expected to require much effort to
obtain the required permits.  Permitting and regulatory
costs are estimated at $2,000 per acre.

3.3.3   Labor Costs
These costs include the cost of personnel at the asphalt
plant, for the truck drivers to transport the mix to the site,
for the crew required to lay and compact the mix at the
site, and supervisory personnel. The cost of equipment at
the asphalt plant and for the paving contractor are included
in the labor cost charged by the contractor. The 3.6-acre
(1.5-hectare) site at TCL required about two 10-hour days
to complete  installation of the 4-inch-thick (10.2-cm)
MatCon™ cover.  The DAFB costs were somewhat lower
because the asphalt plant was close to the site.

According to  WCC, the  labor costs  for MatCon™
installation ranged from $35,000 to $45,000 per acre. Of
this amount, the cost of supervising personnel from WCC
and the site owners was  15 percent, cost of the field crew
was 5 0 percent, cost of the plant personnel was 20 percent,
and the cost of truck drivers was 10 percent.

3.3.4   Supplies and Consumables Costs
3.4    Cost Per Acre of Matcon™ Cover

Based on the cost breakdown discussed in Section 3.3,
the total cost per acre of MatCon™ cover ranges from
$124,000 to $140,000. At the time of this report, WCC's
published catalog price for the  MatCon™ binder and
technical support (including mix design, technical support,
onsite MatCon™ Guide Specification CQC, and related
testing) is $77,400 per acre for a nominal 4-inch thick lift.
The difference between this and the $ 124,000 to $ 140,000
per acre estimate range is directly related to the cost of
the hot-mix aggregates, hot-mix blending, hot-mix haul
from the facility to the job site, lay-down and compaction.
This latter component ($39,600 to $54,600 per acre) is
a function of the local asphalt paving market forces and
proximity of the hot-mix plant to the job site.

This cost compares favorably with the cost per acre of
RCRA Subtitle C covers,  which ranges from $250,000
to $350,000, depending  on the local  availability  of
appropriate soil and drainage materials (Dwyer 1998).
Supplies and consumables costs include the cost of the
proprietary binder, bitumen and the aggregate s required to
prepare the hot mix. The proprietary binder is expensive
since it has not been widely used for hazardous waste
covers. According to WCC, the cost of the binder per acre
of cover is $77,400 (current published catalog pricing),
and the cost of aggregate and bitumen per acre  ranges
from $3,000 to $10,000, depending on the local  cost of
aggregate.
                                                  17

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                                             Section 4
                                    Technology Effectiveness
This section discusses the  two SITE demonstrations
that were conducted to evaluate the effectiveness of the
MatCon™ technology.  This discussion addresses the
construction of the MatCon™ covers, the measurements
that were completed to determine conventional asphalt
and MatCon,™ performance and the demonstration results
and conclusions.

4.1    Description of the Installed Covers

The installation of the MatCon™ cover and the field tests
at the DAFB and TCL sites are discussed below.  The
locations of these two sites are shown in Figure 2-1 (DAFB
site) and in Figures 2-2 and 2-3 (TCL site).

4.7.7  DAFB  Site

This section describes the cover at the DAFB site.

4.1.1.1 Cover Installation

WCC installed the MatCon™ cover system at DAFB in
April 1999. The cap covers 124 by 220 feet (38.4 by 67.1
meters) (see Figure 4-1).  The cover consists of three,
hydraulically independent sections, as follows:

 •  Section I: 12-inch-thick (30.5-cm) MatCon™

 •  Section II:  4-inch-thick  (10-cm) MatCon™

 •  Section III:   4-inch-thick (10-cm)  conventional
    asphalt

A subsurface drainage collection (leak detection) system
was constructed in Section I (Figure 4-2).  The system
consists of a   4-inch-thick  channel  of open-graded
asphalt between two  4-inch-thick  MatCon™ layers.
The subsurface  drainage system divides Section I into
quadrants; the drainage layer beneath each quadrantflows
into a separate  3-inch-diameter (7.6-cm) high density
polyethylene (HOPE) pipe (Figure 4-3).
The area covered by the MatCon™ and conventional
asphalt is  small, so no cold joints were required.  An
elaborate design specification was not prepared for this
site.

WCC contracted  with a local  asphalt contractor to
construct the conventional asphalt and MatCon™ covers.
The 6-inch-thick (15-cm) subgrade was prepared with
crushed rock by  DAFB personnel according  to  the
requirements of WCC.  However, for the 12-inch-thick
(30-cm) MatCon™ section, no crushed rock was used
in the subgrade. The soil was compacted to the grade
specified by WCC, and the asphalt contractor placed
the  12-inch-thick (30-cm) MatCon™ section using  the
material specified by WCC.

The installation was completed in about two days.  WCC
provided the special binder to the local hot mix plant, and
the plant prepared the MatCon™ material according to the
specifications provided by WCC.  WCC prepared a video
of the complete MatCon™ installation and submitted it
to EPA.

4.1.1.2 Drainage  System

A drainage ditch, a metering pit, and a lysimeter sump
were installed during March 2000 to monitor runoff from
the cover and infiltration into the lysimeter section of the
cover. All hydrologic monitoring points were located on
the down gradient side of Section I of the cover.

To monitor surface  runoff, a lined ditch was constructed
along the down gradient side of the cap, and berms were
constructed on three sides to direct the runoff into  the
drainage ditch (Figure 4-4).

The ditch flows into a 4-ft by 4-ft by 4-ft deep (1.2- by
1.2- by 1.2-meter) metering pit (Figure 4-5).  Flow into
the metering pit was measured with a flow meter prior to
surface discharge.
                                                  18

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                                 12"MATCON™
                               with drainage layer
                      4" MATCON™
                                                    4" Conventional Paving Mix
                            -46'-
                                                            -74'-
                                                                                                ^6" Base Course (gravel)

                                                                                                -100'
CD
                             I

                    12" MATCON™
                            3%
                                   1%
                                      \
                II
        4" MATCON™
              1%
                111
4" Conventional Paving Mix
         4" High Barm
  See Figure 2-2
for an enlargement
  of Section I
   Figure 4-1. MatCon™ liner and cover system.

-------
1X3
O
          4" High Barm
B
                          1.5'
         4'x4'x4'
        Metering   2-Turbine
                 Flowmeter
             LEGEND

        |    | Open Grade MATCON™

        |    | Dense Grade MATCON™


   NOT TO SCALE
                                                        -124'-
                                              -60'-
                                                                                                -60"-
                                                -60-
                                                                                                  -60'-
                                                          A'
                                        3" HOPE
                                      Drainage Layer
                                       Manifold and
                                    10" Collection Sump
                                              Asphalt Lined
                                              Drainage Ditch
B" Diameter
Drain Pipe
                                                                                                                         2,5'
                                             B'
                                                                                                                4'
                                                                                  MATCON™ TECHNOLOGY EVALUATION
                                                                                        DOVER AIR FORCE BASE
                                                                                          DOVER, DELAWARE
                                                                                              FIGURE  4-2
                                                                                     LOCATION OF DRAINAGE DITCH
                                                                                           AND METERING PIT
                                                                                                            TETRA TECH EM INC
   Figure 4-2. Location of drainage and metering pit.

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                   3%

             LEAK DETECTION SYSTEM
    :A)	(A-;
                                         ,1%
                                                                   LEGEND
                                                                  OPEN GRADE MATCON™
                                                                  DENSE GRADE MATCON™
                                                              - -^ ;•. •'<"
                                                               •  • ' /t. •
                      3" HOPE
                           LEAK DETECTION SYSTEM
                    B)	(BO
Figure 4-3. MatCon1™ liner and cover cross-sections A-A' and B-B'.

-------
                               4" High x 12" Wide
                                      Berm
 Mounded Soil/
Drainage Divide
                                                                                                                   Backfilled Soil
                                                                                                                8" Diameter Drain Pipe
Figure 4-4. Ditch cross-section.

-------
                                                       •-7            /   6 Wid€
                            6" Wide Ditch
                         12MATCON™
           Berms (4" High)
                                    3%
'I
                            -46'-
                                                    8'
                                                                           -8" Diameter Drain Pipe
                                                                              4"x4'x4' Metering Pit (Cement)
                                                           ^>l / - ^Rip Rap — \ x, s -
                                                          -ls  /X-jx /\-|N /
                                                           — — 1  ^^—1  x ^ — I
                                                                      -12'-
NOT TO SCALE
Figure 4-5. Monitoring pit/french drain.
                                                    23

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To monitor infiltration, the four 3-inch-diameter (7.5-
cm) HDPE pipes leading from the drainage layer were
connected to a 10-inch-diameter (25.4-cm) sump, as shown
in Figure 4-6. Field installation of this sump utilized a
single piece of HDPE pipe.

4.7.2   Tri-County Landfill
MatCon™ was installed at the TCL site in Elgin, Illinois,
by WCC as a final cover system in November 1999. The
project consisted of a 3.6-acre (16,092 m2) site that had
a subgrade previously prepared for WCC's final grading
and subsequent MatCon™ installation. WCC prepared
the final grade for paving, constructed the test section,
and installed the MatCon™ cover over a 2-week period
(Figure 4-7).

As part of the MatCon™ cap installation by WCC for
the TCL site, the patented three-layer  leak detection
system was proposed.  Review of the  system design
by the U.S. Army Corps of Engineers (COE) and their
subsequent comments  required the  incorporation  of
several modifications for the lysimeter that was installed.
Specific changes in the design included the use of aHDPE
membrane liner as the underlying impermeable barrier.
This was placed on top of a panel of conventional asphalt,
over which a geotextile fabric was placed for protection
and cushion purposes. The rounded drainage rock material
was placed over the geotextile fabric as a replacement for
the open-graded MatCon.™ The entire installation was
then covered with the final MatCon™ panel (Figures 4-8
and 4-9). The lysimeter pipe and sump were installed by
Waste Management, Inc. (WMI).

4.1.3   Installation Details
Installation of the MatCon™ covers at both the DAFB and
the TCL sites was observed to document the construction
details and construction quality.

4.1.3.1 Subgrade and Drainage Systems

At the TCL site, the underlying subgrade was firm and
unyielding, and was compacted using conventional heavy
load proof-rolling procedures.  Surface  grades of 1 to
3 percent were used to facilitate drainage of the  final
surface.  The subgrade was inspected and accepted by
WCC personnel. The surface was finish graded to within
the tolerance of ± 0.5-inch (1.2-cm) measured using a 10-
foot (3-meter) straight-edge level prior to paving.
At the TCL site, coarse aggregate placed as the drainage
layer of the lysimeter facilitated the conveyance of water
horizontally but could not be compacted to a firm and
unyielding condition. This resulted in difficulties during
the paving operation.

All retaining sidewalls, piping, and sump appurtenances
were designed to be water tight. Sump design prevented
intrusion from rain and snow (gasketed lid) and included
protection from freezing temperatures, methods to adjust
to barometric pressure changes and minimize condensation
(adequate weatherproof venting), and measures for secure
access (locking lid).

4.1.3.2 Cover Construction Quality

At the TCL site, a crack at a cold joint appeared after a
prolonged period of cold weather in January 2000. The
edge of the asphalt application is typically more difficultto
compact because there is no lateral support for the roller.
When the asphalt is hot, the edges weld together properly.
However, an edge that is allowed to cool overnight is then
very difficult to bond to the next day's first application of
asphalt.  In addition, it is especially difficult to increase
density in the cold joint area.  The result is a zone along
the cold joint that may be poorly compacted. Raveling,
or separation of aggregate particle fines from the surface
or edges  of the compacted asphalt, can occur in these
zones. Although WCC has determined that poor quality
workmanship was the cause, a belter design has since
been developed to overcome the raveling and  reduce
dependency on workmanship.  A wedge-shaped  cold
joint panel (3-meters wide) proved to be a good design
in terms of bonding and providing a good impermeable
mat. The new design includes removal of some material
and a heavy tack coating.

The  crack that appeared at the cold joint at the TCL site
was  routed and sealed.  The zone along the cold joint,
about 3 feet wide (0.91 meter), was sealed with mastic to
decrease the permeability by filling the surface voids.

4.2    Evaluation  Procedures

Procedures used to  evaluate the MatCon™ cover and
compare  it with conventional asphalt were described in
the Technology Evaluation Plan/Quality Assurance Project
Plan (TEP/QAPP) (TetraTech2000). Field sampling ofthe
slabs and cores at the DAFB site was completed in August
1999. Samples were obtained at the TCL site immediately
after cover installation in November  1999, and  then
again in April 2000 to obtain samples in a portion ofthe
                                                  24

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                                                       Slip Cap Cover
UPfc Overtlow Pipe (Outlet)
"^^-^
Mesh Screen
^"\^


Backfilled Soil
Around Pipe
Sump Bottom
HOPE solid cap ""~-\^^




x"
3 i_ 	 Compression Cap
~— Vent Hole
Ground Surface
MATCON™ Cover
•^ 	 Flow from 3" HOPE Pipe (Inlet)
X
Elbow "T"
10-inch diameter HOPE pipe,
jS' Schedule 40 or greater
1

    NOT TO SCALE
Figure 4-6. MatCon™ liner and cover system leak detection sump.
                                                 25

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1X3
05
                  B
                                             3" Diameter
                                          Perforated PE Pipe
                                     MatCon™ Asphalt
                                                                       •80'-
     \    t
3.3% __  ^
2'
                                                B1
 \
4
                      MatCon™ Asphalt with
                     Drainage Channel Below
  3" Diameter
 Non-Perforated
    PE Pipe
                 NOT TO SCALE
   Figure 4-7. Plan view of the MatCon™ cover.

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                                               30"-
                                                    MatCon™ Asphalt
                                                                   4% Slope
                                                                                      MatCon™ Asphalt
                                                 — 3" Diameter Perforated Pipe
                                                         Transitioning to
                                            Non-Perforated High-Density Polyurethane Pipe
                                                   •CoarseAggregate Backfill
                                                         (1 x 10-1 cm/s)
                                                   •16 oz. Geotextile

                                                   -40 Mil LLDPE Geomembrane
                                                   - Conventional Asphalt
                                                   •Prepared Coarse Aggregate
                                                          Base Course
NOTTO SCALE
    Figure 4-8. Section A-A'
                                                  27

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                                       100
                                                                                    MatCon™ Asphalt
                                                                              Install Lysimeter
                                                                                 Pipe Seal
                                                                                  Diameter Non-Perforated
                                                                                   PE Conveyance Pipe
                                                                                  Sloping at Minimum of
                                                                                     1%Toward Sump
                                                                      3" Diameter Perforated
                                                                             PE Pipe
                                            16 oz. Geotextile
                                            40 Mil LLDPE Geomembrane
                                            Conventional Asphalt
                                            Prepared Coarse Aggregate
                                                   Base Course
NOTTO SCALE
 Figure 4-9. Section B-B'.
                                                  28

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MatCon™ cover where a crack was observed. Extensive
testing of slab and core samples from the MatCon™ and
conventional asphalt sections was performed  for the
DAFB site. However, only limited laboratory testing was
performed on the TCL cores.

The sampling methods, field and laboratory tests, and
the quality assurance procedures used for the field and
laboratory testing are detailed in this section.

4.2.7  Field Testing

This section discusses field testing at DAFB and TCL.

4.2.1.1 Basis of Measurement of Field
       Permeability

Field permeability of the MatCon™ was calculated during
periods of rainfall by measuring the drainage volume into
the sump and using Darcy's Law. The permeability (k)
was calculated using the following equation.
              k = QL/Ath

where  Q =    flow into the sump
       L =    nominal thickness of the MatCon™
              cover
       A =    area of the cover
       t =    duration of the test
       h =    hydraulic head (as described below)

The variable ofhydraulic head (h) in the above equation was
based on the reported USGS rainfall amount during each
monitoring period.  However, several assumptions were
required, which caused uncertainties in the calculation (see
Section4.4.1). Therefore, constant-exposurepondingtests
were established to better estimate the field permeability.
For ponding test permeability calculations, hydraulic head
(h) was equal to the thickness of the MatCon™ layer
plus the height of the water ponded on the surface of the
cover. Field measurements of water infiltration into the
MatCon™ cover were completed at the DAFB site from
April through July 2000. In addition, attempts were made
to obtain a hydrologic balance for the DAFB site during
April through June 2000 using a flow meter to measure
runoff from the MatCon™ cover.

4.2.1.2 DAFB Site

Data for the volume of drainage layer infiltration and
surface runoff were collected on a regular basis.  These
data were recorded in a field book, and Tetra Tech
personnel  performed hydrologic calculations.   During
each trip, the drainage layer sump (DLS) was inspected
for integrity, and a water level measurement was taken.
The sump was evacuated for the next measurement. A
flow meter reading was obtained, and the monitoring pit
was pumped out.

Data for the DLS were collected using a measuring tape.
The depth of the water column accumulated in the sump
was recorded in triplicate. The average depth measurement
was then converted to a volume in gallons. This volume
was then used to calculate a permeability  value using
Darcy's law, as described above.

Data from the surface drainage flow meter were more
problematic. Consistent cumulative measurements were
difficult to record due to the recurring heavy rainfall and
subsequent flooding of the site.  Therefore, reliable flow
data could not be obtained.

A 6-hour ponding  test was conducted that consisted of
applying ahead of approximately 2.5 inches (6.2 cm) of
water over the MatCon™ Section I area while monitoring
the flow in the DLS.

4.2.1.3 TCL Site

Monitoring trips were conducted to collect data for the
volume drainage layer  infiltration and surface runoff.
Bi-weekly trips were made to the TCL site  to measure
the water level in the sump. The trip was planned after
a rainfall event of 1  inch  (2.5 cm) or more during the
past 24 hours. After the  measurement, the sump was
bailed out for the next measurement.  Using the sump
water levels,, the drainage volume was determined, and
the permeability of the MatCon™ cover was calculated
using Darcy's law.

A 4-inch-high (10-cm) asphalt berm  was  constructed
around the perimeter of the test section on top of the
MatCon™ cover. In addition, berms were added between
the edge berms, forming a  series of terraces where water
could be impounded. Water from both a tank truck and
heavy rainfall filled the terraces to an average depth of
about 2 to 2.5 inches  (5.1 to 6.2 cm) and was maintained
for almost 48 hours.   During this period, the water
inflow to the sump was monitored and used to calculate
the permeability of the MatCon™ cover. A steady-state
condition was reached in about 6 hours.

4.2.2  Sampling Methods

The objectives of the field sampling program were to obtain
representative samples of the MatCon™ and conventional
                                                 29

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asphalt covers for subsequent laboratory testing. This
section describes the sampling objectives, the sampling
locations, and sampling procedures for the MatCon™and
conventional asphalt covers.

4.2.2.1 Sampling Objectives

The  following  general objectives were used for all
sampling activities:

 •  Collect samples in a manner that ensures they will
    represent the medium being sampled

 •  Maintain proper chain-of-custody  control of all
    samples, from collection to testing

 •  Follow QA/QC procedures appropriate for EPA
    National  Risk  Management Research  Laboratory
    (NRMRL) Applied Research Projects

4.2.2.2 Sampling Locations and Procedures

The cover at the DAFB site was planned to be a long-
term functioning cover, and was not constructed solely
for demonstrations purposes.  Therefore, the sampling
strategy sought to minimize the amount of area impacted
by sample  coring,  so  that repairs to  the cover could
be implemented more  effectively.  It was decided that
confining the sample cores to one subarea of the cover
would still  provide representative samples because the
entire cover was installed in two days using the same work
crew, materials, and procedures for all areas of the cover.
Asphalt core and slab samples were collected from a 3-ft
by 3-ft (0.91-by 0.91-meter) sampling area in Section I
and from 6-ft by 8-ft (1.8- by 2.4-meter) sampling areas
in Sections II and III, as shown in Figure  4-10.  The
number of samples taken in each of the three sections of
the demonstration cover is listed in Table 4-1.

PRI collected samples from the locations shown on Figure
4-10 on August 26 and 27, 1999. A coring machine was
used to obtain the 4-inch-diameter (10-cm)  and 6-inch-
diameter (15-cm) cores, and a diamond-toothed saw was
used to obtain the slab samples. Areas where samples
were collected were then patched with hot mix asphalt
by WCC.

Samples at the TCL site were not obtained from the 30-ft
by 80-ft(9.1-by 24.4-m)test section. They were obtained
instead from an adjacent location where light poles were
to be installed on the cover.  Six cores  were  obtained
initially, and five more cores were obtained in April 2000
at the location of a crack. The only testing that was done
with these cores was aggregate properties, void space, and
hydraulic permeability.

4.2.2.3 Sample Identification and Handling

Samples obtained by PRI Asphalt Technologies, Inc. (PRI)
were identified by location and sample number, and were
packed carefully in padded containers. Chain-of-custody
forms were filled out by PRI to document the acquisition
of the field samples.  The containers were transported by
PRI personnel in a van to PRI's  laboratories in Tampa,
Florida.  The  PRI  personnel in the laboratory signed
the chain-of-custody forms to  document receipt of the
samples.   PRI had custody of the samples from field
acquisition to receipt in the laboratory.

Laboratory tests run on the samples are listed in Table
4-2; a description of each of these tests is provided  in
the TER.

4.2.3 Laboratory Testing

The testing methods selected for the project are those
standardized by the American Society of Testing and
Materials (AS™) and the American Association of State
Highway  and Transportation   Officials   (AASHTO).
Calibration of equipment used to perform the standardized
tests (AS™ and AASHTO) was performed, when required,
as recommended in the procedure (AS™ 1997).

For the flexural test that simulates the effect of differential
settlement on the MatCon™ cover, no standardized test is
available; however, Dr. Ronald Terrel of Terrel Research
devised a test that was used for this demonstration. These
laboratory testing methods are described in further detail
in the Quality Assurance Project Plan (QAPP).

4.2.4 Quality Assurance and Quality
       Control Program

The overall objective for this evaluation was to produce
well-documented data of known quality.   Quality  is
measured by monitoring data precision and accuracy,
completeness, representativeness, and comparability.

The evaluation was designed to ensure that a sufficient
number of samples were collected to represent the cover
material at each given site and  that each  sample was
taken in a manner that ensures  representativeness to the
extent practical.
                                                 30

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       •«*•
       CM
                       I
               12" MATCON™
                            .Seam
                           3"x3"
                          Sampling
                           Area
4" MATCON™
             .Seam
            6'x8'
           Sampling
            Area
4" Conventional Paving Mix
                    -Seam
                   6W
                  Sampling
                   Area
                      -46'-
      -74'-
             -100'-
       NOT TO SCALE
Figure 4-10. Sampling area locations.

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Table 4-1. Cover Sample Type, Numbers, and Labeling-DAFB Site
Sample
Type





Core


Slabs





Core





Slabs

Slabs

Approximate
Size


4" (10 cm)
diameter


6" (15 cm)
diameter
14" x 40"
(35 x 100 cm)

4" (10 cm)
diameter




6" (15 cm)
diameter
14" x 40"
(35 x 100 cm)

14" x 14"
(35 x 35 cm)
Quantity
5
5

5

12

8
4

5
5

5

12

8


4

4

Location



Section III
4" (10 cm)
Conventional
Paving
Mix






Section II
4" (10 cm)
MatCon™




Section I
12" (30 cm)
MatCon™
Label
4-1 through 4-5
5d-l through 5d-5

2a-l through 2a-5

7-1 through 7- 12

2b-l through 2b-8
A, B, C, D

4-1 through 4-5
5d-l through 5d-5

2a-l through 2a-5

7-1 through 7- 12

2b-l through 2b-8


A, B, C, D

A, B, C, D

                                                       32

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Table 4-2. Characterization Testing on Asphalt Samples-DAFB Site
         Parameter
 Sampling
 Location

  Section
I    II   III
Proposed Test
Samples Used
   Hydraulic Conductivity
   Flexural Properties
   Load Capacity/ Deformation
   Shear
   Joint Integrity
   (permeability)3

   Tensile Strength
   Thermal Crack Resistance
     X   X    ASTM D-5084 and
               AASHTO T-283

     X   X    Differential Settling
               Test at 25 °C (one
               month duration)

     X   X    Resilient Modulus
               at 25 °C
               ASTM D-4123

     X   X    Shear Test at 4, 20,
               and 40 and 60 °C
               AASHTO TP 7

     X   X    ASTM 5084


     X   X    AASHTO TP 9
     X   X    AASHTO TP 10
   Degradation and Accelerated       X   X    ASTM D-5084
   Weathering Properties                       AASHTO TP 31
   Voids and Asphalt Binder          X   X
   Content

   Layer Thickness             XXX
   Aggregate Properties              X   X
   Hydraulic Transmissivity     X
   (Drainage layer only)
               ASTM D-3203 and
               AASHTO TP 53

               Direct
               measurement with
               ruler

               ASTM C-136,
               C-131,C-127,
               D-2172

               Modified ASTM
               D-5084
                    4" diameter cores, 3 replicates


                    4" x 4" x 3 6" slab2
                    2 replicates


                    4" diameter cores,
                    3 replicates


                    6" diameter cores, 2 replicates
                    per temperature per section


                    4" diameter cores, 3 replicates


                    4" x 4" x 10" slab2,
                    3 replicates

                    4" x 4" x 10" slab2,
                    3 replicates

                    4" diameter cores
                    Aged using  water, ultra-violet
                    light, and kerosene. Tested at
                    initial, 1  week, 1 month, and 2
                    months, 2 replicates

                    4" diameter cores, 3 replicates


                    cores and slabs,
                    3 replicates


                    4" diameter cores,
                    3 replicates


                    12" x 12" x 12" slabs2,
                    2 replicates
   Notes:
   1      Cores from the TCL site were analyzed for hydraulic conductivity only
   2      Slabs were cut to size using a diamond-toothed saw
   3      After cracking and prior to j oint repair
                                                33

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The comparability of the data was maximized by using
standard AS™ and AASHTO methods.  Comparability
was also maximized through the use of consistent sample
collection techniques and field measurement methods
throughout the evaluation.

4.2.4.1 Field Quality Control  Program

Field quality control procedures consisted of a water-level
meter precision check atthe TLC site. This quality control
check was not implemented at the DAFB site because a
measuring tape was used to obtain the depth to water. After
each field measurement event, the following precision-
check procedure was executed. First, a graduated cylinder
was fitted with a measuring scale divided into 0.10-inch
(0.25-cm) increments.  The vessel was then filled with
water and the field water-level meter was used to obtain a
measurement in the vessel. This measurement was taken
three times. If the three measurements agreed within 0.1-
inch (0.25-cm) of each other, the water-level meter was
considered acceptable.

Each water-level measurementtaken in the sump was taken
three times to ensure precision. These three measurements
were then used to calculate the relative percent difference
(RPD).  The measurements were accepted if they met
the criteria of being less than a RPD of 2.  If accepted,
the three values were averaged and used to calculate the
MatCon™ permeability.

The accuracy of the in-line volumetric flow meter was
determined by field checking using a bucket and stopwatch
method.  The procedure required that flow occurred at
the time of the field check, thus these checks had to be
executed during rain events. The beginning flow rate
registering on the flow meter was recorded to start. Then
a 3-gallon (11.4-liter) bucket was filled at the outflow
of the  runoff  discharge pipe while elapsed time was
measured. The volume was then divided by the elapsed
time to give a rate, which was compared to the rate read
from the flow meter. Lastly, the  rate was again read from
the flow meter to ensure consistency in readings.  If the
difference between the flow  meter and the bucket and
stopwatch estimation was within 5 percent, the flow meter
was considered accurate.

4.2.4.2 Laboratory Quality  Control Program

PRI completed all the laboratory tests listed in Table
4-2 to characterize the cover materials at each site and
to compare the MatCon™ cover with the conventional
asphalt cover at the DAFB site. In conjunction with these
physical testing procedures, PRI routinely performed a
number of QC checks that are detailed in the QAPP (Tetra
Tech 2000).

Calibration of the test equipment was performed, where
required, and records maintained at PRI. For the air voids
and binder property measurement,  standard AASHTO
specimens were used. Results obtained were within two
standard deviations of the mean published by the Asphalt
Materials Reference Library (AMRL) proficiency standard
samples.  The AMRL  is maintained by the National
Institute of Standards.  Except for the shear test data, all
other test data were within the acceptance criteria detailed
in the QAPP. Due to equipment malfunction at the Auburn
University laboratory (PRI's subcontractor), the shear test
data were unacceptable.

Laboratory data were checked regularly for consistency
with the expected result. For example, when the laboratory
permeability results of the  MatCon™ samples were
significantly greater (greater than 1 x 10~6cm/sec) than the
expected value of 1 x 10~8 cm/sec, analyses of the air void
percentage  of the samples were found to be higher than
the expected value of 3 percent. Air void percentage is a
primary factor in the performance of the MatCon cover.
In a real-world landfill cover application project, void
percentages of greater than 3 percent would warrant the
re-installation of the cover.  Therefore, for the purposes
of this  demonstration, additional cores were obtained
from the MatCon™ slab sample and analyzed for  air
void percentage. Based on these results, a re-analysis
of permeability was conducted on core samples with 3
percent or  less air  void  percentage. These results are
presented in Section 3.0.

4.3     SITE Demonstration Results and
        Conclusions

The results of the evaluation are presented below in relation
to the primary and secondary objectives established for
the evaluation in the TEP/QAPP. Primary (P) objectives
are considered critical  for the technology evaluation,
and secondary (S) objectives provide additional useful
information.

PI—Determine if the MatCon™ cover exhibits a field
permeability of less than the RCRA Subtitle C requirement
of 10~7 centimeters per second (cm/sec).

To estimate the field permeability of the MatCon™ cover,
the volume of infiltration during individual rainfall events
was measured over the 6-month demonstration period at
                                                  34

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each of the two sites.  Using Darcy's Law, the measured
infiltration rates were converted into estimates of field
permeability, and these estimates were compared to the
regulatory requirement.

The  in-field permeability calculated from  measured
infiltration for the MatCon™ covers at the DAFB and TCL
sites is provided in Table 4-3. The table indicates that
the in-field permeabilities are up to 3 orders of magnitude
lower than the requirement for RCRA Subtitle C landfill
covers.

P2—Compare  the  laboratory-measured permeability
andflexural properties of the MatCon™ cover and the
conventional asphalt cover at the DAFB site.

The  vendor claims that the  MatCon™ cover is both
less  permeable and  has superior flexural properties
when compared to conventional asphalt.  To test these
claims, laboratory tests that evaluate the two properties
were conducted on both MatCon™  and conventional
asphalt samples from the DAFB site.  Results for each
parameter were then comparedusing descriptive statistics
to determine whether the MatCon™ cover appears to be
superior to conventional asphalt for these two critical
parameters.
Table 4-4 provides a summary of the laboratory properties
of MatCon™ and conventional asphalt. As shown in this
table, the average permeability of MatCon™ was about
four orders of magnitude lower than that of conventional
asphalt. The flexural tests of the MatCon™ cover samples
indicate that a 36-inch-long (91.4-cm) beam can sustain
20.41 millimeters of deflection without cracking, whereas
conventional asphalt cracked at  7 to 10 millimeters of
deflection.  Further, the MatCon™ cover sample had no
cracks  under 20 millimeter of deflection, whereas the
conventional asphalthad 3-millimeter-wide, 2.5-cm-long
cracks  at about 25 millimeter of deflection.

SI—Measure  other   laboratory-measured  physical
properties of the MatCon™ cover and the conventional
asphalt cover at the DAFB site

The vendor makes no  specific claim for the superiority
of MatCon™ to conventional asphalt with respect to
physical parameters other than permeability and flexural
properties.   However, differences   in other physical
properties that can be measured in the laboratory may be
of interest to potential users. Therefore, samples of both
the MatCon™ cover and the conventional cover were taken
Table 4-3. Estimated In-Field Permeability of MatCon1™ Cover During Rainfall Events*
                   Period Ending    Measured Leakage        Calculated
                                        Volume (m3)     Permeability (cm/sec)
Dover Air Force Base
07-Apr-OO
17-Apr-OO
27-Apr-OO
09-May-OO
16-May-OO
26-May-OO
09-Jun-OO
Tri-County Landfill
20-May-OO
02-Jun-OO
7-Jul-OO
21-Jul-OO

3.3E-02
6.4E-03
6.2E-02
6.4E-03
6.3E-02
6.3E-02
6.3E-02

2.8E-03
5.9E-04
2.7E-03
9.4E-03

4.5E-08
1.3E-08
1.3E-07
2.6E-08
1.3E-08
8.5E-08
8.5E-08

1.9E-09
5.2E-10
3.4E-09
1.5E-08
                    * At each site, a ponding test was also conducted to measure
                     in-field permeability.
                                                  35

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Table 4-4. Statistical Summary of Laboratory Data.
Parameter MatCon™ Asphalt
No. of Mean Std. Min. Max. No. of
Samples Dev. Samples
Tri County
Landfill 4 1.55 0.87 0.25 2.1
(TCL) Void
Space, %
TCL <1.0 <1.0 <1.0
Hydraulic 7 x O2 x x -
Conductivity 10'8 10'8 10'8
(cores) cm/sec
DoverAir <1.0 <1.0 <1.0
Force Base 4 x O2 x x 3
(DAFB) 10-8 10-8 10-8
Hydraulic
Conductivity
(cores)
Flexural
Properties at
Center, 2 18.96 2.08 17.51 20.41 2
Deflection in
mm

Joint Integrity 3 5.47 2.02 x 4.3 x 7.5 x 3
cm/sec xlO-5 lO'5 10'5 10'5
Conductivity
after
Accelerated 3 7.35 6.05 x 1.65 x 1.37 x 3
Weathering x 10'9 10'9 10'9 10'8
30 days,
cm/sec
Conductivity
after
Accelerated 3 2.2 x 3.8x 3.9 x 6.6 x 3
Weathering 10'6 10'6 10'9 10'6
60 days,
cm/sec
Fuel
Resistance
(Kerosene) 8 1.5 0 1.5 1.5 8
Depth of
Penetration,
cm
Conventional Asphalt
Mean Std. Min. Max
Dev.

_ _ _



_ _ _


1.04
x 1.5 x 1.8 x 2.75
lO-4 lO-4 10-5 xlO-4





31.25 7.54 25.92 36.58


1.04
x 1.5 x 1.8 x 2.75
lO-4 10-4 io-5 10-4

2.96
x 2.89 x 2.65 x 3.22
lO-4 1Q-4 10-4 10-4



3.15
x 1.32 x 1.77 x 4.41
lO-4 io-4 io-4 xio-4




5.5 0.53 5 6



36

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Table 4-4. Statistical Summary of Laboratory Data (continued).
Parameter                  MatCon™ Asphalt

               No. of               Std.
              Samples    Mean    Dev.    Min.
                                                                      Conventional Asphalt
       No. of            Std.
Max   Samples Mean    Dev.
                                                                                       Min.   Max.
DAFB
Void Space,     4
                           1.53      0.33   1.25    1.89
                 10.53    1.17       9.2    12.7
Coarse
Aggregate       3        2.74     0.01   2.73    2.75      3      2.75     0.03      2.72    2.78
Specific
Gravity

Fine
Aggregate       3        2.72     0.01   2.71    2.72      3      2.74     0.01      2.73    2.74
Specific
Gravity
from the DAFB site and analyzed for various parameters
pertinenttothe physical performance of asphalt paving and
covers.  Results for each parameter were then compared
using descriptive statistics to determine if there are any
significant differences between the two types of covers.

The physical properties measured to satisfy objective S1
are listed below:

 •  Joint integrity

 •  Load capacity and deformation

 •  Shear strength

 •  Tensile strength

 •  Thermal crack  resistance

 •  Aging and degradation properties

 •  Void space

 •  Aggregate properties


S2—Determine whether extreme weather conditions or
vehicle loads affect the field performance of the MatCon™
cover
  To evaluate this objective, the MatCon™ covers at both
  sites were inspected periodically in the field, particularly
  following periods of extreme cold or other adverse weather
  conditions, to  assess whether  any cracks or surface
  deformities developed. These field inspections were used
  to evaluate the effects of extreme weather or vehicle loads
  since the previous inspection. General information on use
  of the covers for parking and on recent weather events was
  collected from the site owners and evaluated against any
  deformities noted in the field inspections.  The TCL site
  in Elgin, Illinois, encountered much colder temperatures
  than the DAFB site in Dover, Delaware.  As a result,
  data on the impacts of extreme cold were observed only
  at the TCL site.

  At the TCL site, WMI parked their garbage trucks during
  the night and their waste recycling trucks traveled over the
  MatCon™ cover during the day. Further, the MatCon™
  cover was subjected to extremely cold, sub-zero weather
  during January through March  2000. In late January,
  a crack was observed on the cover surface.  This was
  investigated by taking core samples at the crack location
  and obtaining nuclear density measurements in the vicinity
  of the crack. Except for the core sample on the  crack
  that had developed at a cold joint, all samples showed a
  permeability in the  range of 10~7 cm/sec to 10~9 cm/sec.
  The sample on the crack had 8.2 percent air voids and a
                                                  37

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permeability of 3.56 x 10'5 cm/sec, indicating it was poorly
compacted due to inadequate field quality control.

Based on the investigation, WCC improved the design
and construction procedures for cold joint construction for
MatCon™ covers. The crack was repaired by routing the
j oint, cleaning the j oint using a hot air lance, and extruding
it full of hot modified asphalt mastic joint sealer. Apart
from the crack that developed at the cold joint, the rest
of the MatCon™ cover performed well under extreme
weather conditions and vehicle loads.

S3—Estimate a cumulative hydrologic balance for  the
MatCon™ cover over the period of the demonstration at
the DAFB site

A hydrologic balance for the cover system was estimated
at the DAFB site. The hydrologic balance was based on
cumulative precipitation, totalized surface runoff, and
subsurface drainage overthe entire 6-month demonstration
period. Although the hydrologic balance is approximate
because of the length of time involved, it may provide
additional insights into the performance of the MatCon™
cover.

Theoretically, the infiltration into the MatCon™ cover
could be determined by using the equation
I = P - ET - Qs, where

 I   = Infiltration

 P   = Precipitation volume

 ET = Evapotranspiration from the MatCon™ surface

 Qs  = Runoff

However, heavy precipitation events resulted in flooding
and precluded accurate measurement of surface runoff.
Therefore, a hydrologic balance for the DAFB site could
not be obtained in this manner.

S4—Estimate the cost for constructing the MatCon™
cover and maintaining the cover for the duration of the
demonstration

The  capital and operating costs for the MatCon™ cover
technology, as demonstrated at both the DAFB and TCL
sites, were estimated based on cost information obtained
from WCC and reviewed by Tetra Tech. The costs of the
MatCon™ installation are detailed in Section 3.0 of this
report.
4.4     Discussion of Results

A discussion of the field and laboratory measurements
affecting MatCon™ performance is provided below.

4.4.1   Discussion of Field Data

The measured field permeability varied from a high value
of 1.28 x 10"7 cm/sec to a low value of 5.15 x 10~10 cm/sec.
The field permeability data calculations were based on
several assumptions and Darcy's law.  The uncertainties
in the calculations included the following.

 •  The head was based on measured precipitation over
    the entire site; however, the MatCon™ surface was
    not subjected to the uniform head assumed for the
    precipitation event. Most of the precipitation did not
    remain on the surface, except for the  two ponding
    tests.

 •  Infiltration  measured as water volume in the sump
    does not account for changes  in the water retained
    in the drainage layer.

 •  There was uncertainty at the DAFB site about the
    measurement of infiltration into the drainage layer.
    The  high  groundwater table  at  the  site resulted
    in  flooding, and there is a possibility that water
    infiltrated through the sidewalls of the sump.

To  minimize uncertainties, a  ponding test  was then
conducted  at the TCL  site during a 48-hour period.
Oversight was provided by COE and EPApersonnel. This
resulted in a measured permeability value of 5 x 10~8 cm/
sec. This value is higher than that obtained during rainfall
events probably because during rainfall events a consistent
hydraulic head is not maintained.  The water head was
maintained on the MatCon™ surface more consistently
during  the ponding test. The ponding test at the DAFB
site yielded a result of 1.25 x 10~8 cm/sec.

4.4.2   Laboratory Data

The laboratory data presented in Table 4-4 and elaborated
in this  section provide a comparison of MatCon™ and
conventional asphalt. As discussed in Sections 4.4.1 and
4.4.2, the primary physical properties that were studied
included permeability and flexural properties, and the
secondary physical propertiesthatwere measured included
thermal crack resistance, load capacity and deformation,
tensile  strength, and aging and degradation properties.
These properties are discussed below.
                                                  38

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4.4.2.1 Permeability

Permeability  is  a critical parameter determining the
performance of the MatCon™ cover. Table 4-4 indicates
that the laboratory permeability of MatCon™ is about
four orders of magnitude lower than conventional asphalt,
and is less than 1 x 10~8 cm/sec. This is due to the lower
void space and higher density of MatCon™ compared to
conventional asphalt.

4.4.2.2 Flexural Properties

The  ability of MatCon™ to  settle over potential voids
in the underlying materials isan important characteristic
when considering caps over  fills associated with waste
materials.  Most traditional tests for highway engineering
do not consider flexural behavior that can occur with high
strains in these settings. Consequently, a specialized test
was used in this study to consider large strains.

Comparative data for MatCon™ and conventional asphalt
are presented in Figure 4-11. This figure illustrates the
total deflection versus time  with notes indicating the
onset of cracking. In all cases, the conventional material
started cracking  before the total deflection reached 15
millimeters, while the MatCon™ did not crack even at
deflections as large as 20 millimeters.  This increase in
strain tolerance is attributed to the improved binder that
is used in the MatCon™ system.  The data collected
demonstrate that MatCon™ is able to experience larger
strains and deflections than conventional asphalt without
cracking.

4.4.2.3 Load Capacity and Deformation

Introducing a  loading stress, such  as the weight of a
vehicle, causes strains in the asphalt structure.  These
strains can lead to premature failure if the structure is not
designed adequately. Two modes of failure are generally
considered for the design of asphalt structures, which are
dependent upon the resilient properties of the materials: (1)
fatigue failure is dependent on resilient modulus/stiffness
and fatigue properties of the materials and (2) permanent
deformation, which is controlled by the aggregate interlock
and high temperature properties of the binder.

Load capacity is determined by assessment of the resilient
modulus over a range of conditions, and the permanent
deformation behavior is measured with shear testing.

The  resilient modulus was measured for temperatures
ranging from  -20 °C to +80 °C.   The modulus of
MatCon™ was 2048 MPa compared to 3200 MPa for the
conventional asphalt. The reduced resilient modulus of
the MatCon™ was due to the use of a modified binder that
is more flexible at the lower temperatures applied in the
resilientmodulustest. However, athighertemperatures,the
modulus of the MatCon™ exceeded that for conventional
asphalt. This indicatesthatMatCon™performs acceptably
over a wider range of temperatures than conventional
asphalt for distress modes such as cracking (at lower
temperatures) and permanent deformation and rutting (at
higher temperatures).

4.4.2.4 Tensile Strength

Tensile strength affects cracking due to thermal- or load-
related effects. The tensile strength of asphalt materials
varies with temperature, time of loading, and magnitude
of strain. High stiffness materials are subjected to more
stress at lower temperatures, and hence can be more
susceptible to cracking.

The low temperature tensile properties of MatCon™ and
conventional asphalt are shown in Table 4-5.  The data
show that the tensile  strength of the MatCon™ material
is approximately 50 percent greaterthan for conventional
asphalt, and that the expected  cracking temperature is
approximately 5 to 7  °C lower.

The tensile properties of MatCon™ indicate that it should
be more resistantto the formation of cracks over the range
of temperatures anticipated in  a landfill surface cover.
Of particular importance is the low-temperature tensile
properties, since asphalt materials generally crack at these
temperature extremes. At low temperatures, MatCon's™
tensile properties enable  it to be used in significantly
harsher climatic regions without the risk of cracking.

4.4.2.5 Thermal Crack Resistance

As asphalt materials cool, the natural tendency is for
the material to attempt to contract  as a  function of
the coefficient of thermal expansion.  However,  the
contraction is effectively prevented  by  the  structure;
consequently, thermal stress builds in the asphaltic material
as the temperature drops.  The increase in thermal stress
eventually results in fracture if the tensile strength of the
material is exceeded.

The asphalt binder choice has the most significant impact
on thermal  crack  resistance.  Other factors, such as
aggregate choice and subgrade type,  affect the density
and degree of cracking after cracks have started.
                                                   39

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         40
         35
         30
         25
|>H
?
         1  r2 = 0.9962
       C,2  r2 = 0.9816
       M,1 r2 = 0.9952
       M,2 r2 = 0.9835
                        Very wide cracks
                       Extra cracks forms
                     3rd hairline crack develops
                         2nd crack, 2cm long
                     1 Hairline crack, 1cm long 7
            Crack 3mm wide, 2.5cm long
            Crack 0.4mm wide, 2.5cm long^
            Crack 0.4mm wide, 1.5cm long
            1 Hairline crack, 1cm long
                                      15       20
                                       Time (days)
Source: PRI Asphalt Technologies, Inc. 2000*
Figure 4-11. Curves showing deflection versus time.
Table 4-5. Tensile Properties for Binder and Mixture at Cold Temperatures
                                                                     Cracked
 ^^^^y   x
^*7X
                                                                     Cracked
                                                          • Com/., Rep. 1 - C,1
                                                               ., Rep. 2 - C,2
                                                          • MatCon, Rep. 1 - M,1
                                                          A MatCon, Rep. 2 - M,2
                                                  25
                   30
35
                                   Tensile Properties Derived from Tests On:
      Property
                              Binder
              Mixture
                           Conventional
                             Asphalt
      Tensile Strength (MPa)     1.86
      Fracture Temperature (°C)  -18.8
                                   MatCon™  Conventional   MatCon™
                                                 Asphalt
                                      2.97        2.579        3.551
                                     -25.7        -25.4        -29.7
                                          40

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The results obtained are presented in Figure 4-12.  The
MatCon™  samples had a higher fracture strength (by
37 percent) and a 4.3 °C  lower fracture temperature
than conventional asphalt. The test results indicate that
MatCon™ has improved low temperature behavior and
will resist  thermal cracking better than conventional
asphalt.  The degree of improvement in both  fracture
strength and temperature is attributed to the modified
binder.

4.4.2.6 Aging and Degradation Properties

Aging of asphalt materials is caused by several chemical
and  physical  processes,  especially  oxidation  and
volatilization. Volatilization isthe loss of lighter molecular
weight fractions through evaporation  that begins  with
distillation  of  crude oil.  Removal of lighter fuel oils
leaves heavier residue, including asphalt. Further refining
and processing results  in a stable base asphalt cement
that is then engineered for various uses, such as paving
and roofing. The quality of asphalt is governed largely
by the source of crude oil, and the only sources used for
MatCon™  are those in which long term stability and
further volatilization are minimized. These properties are
evaluated using standardized test protocols. The mass loss
of volatile material in a standard laboratory test is almost
immeasurable for high  quality asphalt and is essentially
nil over the multi-year life expectancy of pavements.

For very dense, low void MatCon™ mixtures made with
modified asphalt, the expectation is for longevity much
greater than for conventional pavements. Several factors
contribute to this expectation, including the use of base
asphaltthat was selected for superior aging characteristics,
use of modifiers that chemically enhance resistance to
degradation, and the low voids that prevent intrusion of air
and water.  The accelerated weathering tests used in this
study were adapted from the roofing industry, in particular
the International Conference of Building Officials (ICBO),
which typically attempts to predict performance of asphalt
roofing materials. However, any attempt to predict the
actual service  life of MatCon™ based on this testing
would be speculative because of the many variables and
the heretofore unknown performance of MatCon.™ The
approach used in this study is to compare the behavior
between  MatCon™ and conventional  pavement on  a
relative basis, both in the laboratory and by monitoring
field performance over several years.

The aging of asphalt materials is affected by a number
of parameters such  as binder  quality,  mixture  type,
and climate. However, if a system is made effectively
impermeable, the supply of oxygen needed to age-harden
the binder is effectively restricted. MatCon™ materials are
designed to achieve a low permeability and consequently,
aging is anticipated to be low. For all conditions tested,
the resilient modulus of the MatCon™ does not exceed
that of the conventional asphalt. The low void space and
higher binder content in MatCon™ results in the better
aging properties observed for MatCon™ compared to
conventional asphalt.

Accelerated aging provides an insight into how MatCon™
asphalt will perform over its expected life. The accelerated
aging test method is used to determine changes in asphalt
material and performance properties after 30 and 60 days of
exposure to cycles of ultraviolet light and water sprays. In
the accelerated aging study, the slab sections were placed
in an accelerated weathering chamber and left exposed
to cyclic ultraviolet light (20 hrs) and water sprays (3.5
hrs)  with a surface temperature of approximately 160
°F. After 30 and 60 days, specimens were evaluated for
changes in binder properties due to ultraviolet light and
water exposure.

Results of binder property changes were reported as a PG
rating, which is the performance window of the asphalt
between a high and low temperature  that the binder is
expected to perform without cracking.  The PG rating
is the key component for long-term performance  at the
high service temperature for properties indicative of a
susceptibility to deformation, such as  rutting, and at the
low  service temperature  for properties that forecast a
susceptibility to fatigue and thermal cracking. A grading
system for asphalt was developed by the highway industry
and has  been adapted by AS™ (AS™ D-6373).

The accelerated aging tests indicated that the MatCon™
binder was essentially unaffected by exposure to ultraviolet
light, maintaining the same performance grade, PG 82-22,
after 60  days of aging, whereas the conventional asphalt
binder lost both high and low temperature performance
grades upon exposure, going from the initial PG 82-22 to
PG 76-16 after 60 days of accelerated aging. The change
in PG rating of the conventional binder indicates the binder
has lost stiffness and elastic modulus at high temperatures
and flexibility and pliability at low temperatures.  The
loss  at low temperature is also indicative of a binder's
aging rate.

Review  of the  binder properties after exposure  to
cyclic water  sprays  shows the MatCon™  binder has
a wider performance grade, PG 88-21  (109 °C), than
                                                   41

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    Fracture Stress
         (MPa)
      Temperature
                                      Conventional             MatCon

                                                Material Evaluated
Figure 4-12. Fracture stress (MPa) and temperature (°C) for MatCon™ and conventional material.

                                          42

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the conventional binder, PG 82-19 (101 °C).  The low
temperature properties after aging also indicate that the
MatCon™ binder has an improved  resistance to low
temperature thermal cracking. A top to bottom profile
comparison indicated  that the exposure to water had
minimal effect on the binder properties.

As seen  from the data presented in  Table  4-4,  the
permeability of the conventional cover remained generally
unchanged after accelerated aging. The permeability of the
MatCon™ cover increased by an average of two orders of
magnitude, but remained one to two orders of magnitude
lower than that of the conventional cover. The degradation
of the MatCon™ after continued exposure to kerosene was
1.5 cm (out of a total 10-cm thickness).  Under similar
conditions, conventional asphalt degraded by an average
of 5.5 cm (out of atotal of 10-cm thickness).
                                                  43

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                                             Section 5
                                        Technology Status
This section of the report describes commercial availability
and quality  control  requirements for the MatCon™
technology.

5.1    Commercial Availability

The first MatCon™ cover over incinerator fly ash was
installed in Ferndale, Washington, in 1989. This cover
maintains low permeability (less than 10-8 cm/sec) after
12 years of active use as a surface for material staging
and heavy equipment operation. Since then, MatCon™
has been  approved by state regulating agencies  for
projects in Delaware, Illinois, California, Florida, Texas,
New Mexico, and Kentucky, the states where it has been
presented by WCC.

The proprietary binder available from WCC can be shipped
to any hot mix asphalt plant in the country. The MatCon™
mix is prepared at the hot mix plant under the  strict QC
specifications provided by WCC. Therefore, MatCon™
technology is commercially available  throughout  the
United States.

5.2    Construction Quality Assurance
       Requirements

Based on the TCL proj ect findings, the key areas requiring
special attention during future MatCon™ installations are
described below.

 •  Adequate scheduling to allow for input on subgrade
    design, followed by planning and coordination for
    subsequent in-field construction progression

 •  Subgrade construction and preparation to ensure firm
    and unyielding conditions that will allow for proper
    MatCon™ compaction and facilitate proper drainage
    from the final MatCon™ surface

 •  Monitoring MatCon™ hot-mix temperature s prior to
    installation for material acceptance or rejection
Hourly in-field inspection and acceptance or rejection
of compacted MatCon™ based upon frequent and
mapped field density measurements

Construction and workmanship of cold joint panels
assuring compaction and sealing

Design, construction, and workmanship of any leak
detection or lysimeter structures

Provisions for quality control inspection technicians
to monitor, inspect, report, and either accept or reject:
subgrade conditions prior to paving; lysimeter or
leak detection systems; MatCon™  hot-mix  plant
operations; MatCon™ hot-mix transfer and paving
activities; MatCon™ panel compaction and resultant
field densities; and cold joint construction methods
and sequences
                                                  44

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                                           Section 6
                                          References
American Association of State Highway and Transportation
    Officials (AASHTO). 2000. Standard Specifications
    for Transportation  Materials  and Methods of
    Sampling and Testing, 20th Edition. AASHTO, 444
    North Capital Street, Washington, DC.

American  Society  for Testing  and  Materials  (AS™).
    1997.  Annual Book of AS™ Standards.  Volume 4
    (Construction). AS™. West Conshohocken, PA.

Code of Federal Regulations (CFR). 2002.  40 CFR
    Section 264.301.  Subpart N - Landfills, Design and
    Operating Requirements. July.

Dwyer, S.F.  1998.  Construction Cost of Six Landfill
    Cover  Designs  Sandia National  Laboratories.
    Albuquerque, New Mexico. September.

Tetra  Tech  EM  Inc.  (Tetra  Tech).    2000.
    Technology Evaluation  Plan/Quality Assurance
    Project Plan (TEP/QAPP), Wilder Construction
    Company's MatCon™ Technology Evaluation at the
    Lindane Source Area Site, West Management Unit,
    Dover Air Force Base, Dover Delaware, and Tri-
    County Landfill, Elgin, Illinois.February 8.

Wilder  Construction Company  (WCC).   1998.
    Dover  AFB, DE,  Lindane  Source  Area SITE
    Demonstration Program Application.
                                               45

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